diff --git a/composer.json b/composer.json
index a836dea..daa8fd0 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,7 @@
         "ext-curl": "*"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.8.*",
+        "phpunit/phpunit": "3.7.*",
         "squizlabs/php_codesniffer": "3.*"
     },
     "support": {
diff --git a/lib/RetailCrm/Methods/V3/Customers.php b/lib/RetailCrm/Methods/V3/Customers.php
index d44dd72..796f749 100644
--- a/lib/RetailCrm/Methods/V3/Customers.php
+++ b/lib/RetailCrm/Methods/V3/Customers.php
@@ -56,7 +56,7 @@ trait Customers
 
         return $this->client->makeRequest(
             '/customers',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -83,7 +83,7 @@ trait Customers
 
         return $this->client->makeRequest(
             '/customers/create',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['customer' => json_encode($customer)])
         );
     }
@@ -109,7 +109,7 @@ trait Customers
 
         return $this->client->makeRequest(
             '/customers/fix-external-ids',
-            $this->client::METHOD_POST,
+            "POST",
             ['customers' => json_encode($ids)]
         );
     }
@@ -136,7 +136,7 @@ trait Customers
 
         return $this->client->makeRequest(
             '/customers/upload',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['customers' => json_encode($customers)])
         );
     }
@@ -160,7 +160,7 @@ trait Customers
 
         return $this->client->makeRequest(
             "/customers/$id",
-            $this->client::METHOD_GET,
+            "GET",
             $this->fillSite($site, ['by' => $by])
         );
     }
@@ -196,7 +196,7 @@ trait Customers
 
         return $this->client->makeRequest(
             sprintf('/customers/%s/edit', $customer[$by]),
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite(
                 $site,
                 ['customer' => json_encode($customer), 'by' => $by]
diff --git a/lib/RetailCrm/Methods/V3/Orders.php b/lib/RetailCrm/Methods/V3/Orders.php
index b7b9147..56bd6bc 100644
--- a/lib/RetailCrm/Methods/V3/Orders.php
+++ b/lib/RetailCrm/Methods/V3/Orders.php
@@ -57,7 +57,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -84,7 +84,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/create',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['order' => json_encode($order)])
         );
     }
@@ -110,7 +110,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/fix-external-ids',
-            $this->client::METHOD_POST,
+            "POST",
             ['orders' => json_encode($ids)
             ]
         );
@@ -141,7 +141,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/statuses',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -168,7 +168,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/upload',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['orders' => json_encode($orders)])
         );
     }
@@ -192,7 +192,7 @@ trait Orders
 
         return $this->client->makeRequest(
             "/orders/$id",
-            $this->client::METHOD_GET,
+            "GET",
             $this->fillSite($site, ['by' => $by])
         );
     }
@@ -228,7 +228,7 @@ trait Orders
 
         return $this->client->makeRequest(
             sprintf('/orders/%s/edit', $order[$by]),
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite(
                 $site,
                 ['order' => json_encode($order), 'by' => $by]
@@ -260,7 +260,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/history',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
diff --git a/lib/RetailCrm/Methods/V3/Packs.php b/lib/RetailCrm/Methods/V3/Packs.php
index 620222e..c493ce3 100644
--- a/lib/RetailCrm/Methods/V3/Packs.php
+++ b/lib/RetailCrm/Methods/V3/Packs.php
@@ -56,7 +56,7 @@ trait Packs
 
         return $this->client->makeRequest(
             '/orders/packs',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -83,7 +83,7 @@ trait Packs
 
         return $this->client->makeRequest(
             '/orders/packs/create',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['pack' => json_encode($pack)])
         );
     }
@@ -117,7 +117,7 @@ trait Packs
 
         return $this->client->makeRequest(
             '/orders/packs/history',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -141,7 +141,7 @@ trait Packs
 
         return $this->client->makeRequest(
             "/orders/packs/$id",
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -164,7 +164,7 @@ trait Packs
 
         return $this->client->makeRequest(
             sprintf('/orders/packs/%s/delete', $id),
-            $this->client::METHOD_POST
+            "POST"
         );
     }
 
@@ -190,7 +190,7 @@ trait Packs
 
         return $this->client->makeRequest(
             sprintf('/orders/packs/%s/edit', $pack['id']),
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['pack' => json_encode($pack)])
         );
     }
diff --git a/lib/RetailCrm/Methods/V3/References.php b/lib/RetailCrm/Methods/V3/References.php
index d336453..4b9279b 100644
--- a/lib/RetailCrm/Methods/V3/References.php
+++ b/lib/RetailCrm/Methods/V3/References.php
@@ -40,7 +40,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/countries',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -57,7 +57,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/delivery-services',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -82,7 +82,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/delivery-services/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['deliveryService' => json_encode($data)]
         );
     }
@@ -100,7 +100,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/delivery-types',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -125,7 +125,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/delivery-types/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['deliveryType' => json_encode($data)]
         );
     }
@@ -143,7 +143,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/order-methods',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -168,7 +168,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/order-methods/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['orderMethod' => json_encode($data)]
         );
     }
@@ -186,7 +186,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/order-types',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -211,7 +211,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/order-types/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['orderType' => json_encode($data)]
         );
     }
@@ -229,7 +229,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/payment-statuses',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -254,7 +254,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/payment-statuses/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['paymentStatus' => json_encode($data)]
         );
     }
@@ -272,7 +272,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/payment-types',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -297,7 +297,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/payment-types/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['paymentType' => json_encode($data)]
         );
     }
@@ -315,7 +315,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/product-statuses',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -340,7 +340,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/product-statuses/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['productStatus' => json_encode($data)]
         );
     }
@@ -358,7 +358,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/sites',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -383,7 +383,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/sites/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['site' => json_encode($data)]
         );
     }
@@ -401,7 +401,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/status-groups',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -418,7 +418,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/statuses',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -443,7 +443,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/statuses/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['status' => json_encode($data)]
         );
     }
@@ -461,7 +461,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/stores',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -492,7 +492,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/stores/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['store' => json_encode($data)]
         );
     }
diff --git a/lib/RetailCrm/Methods/V3/Statistic.php b/lib/RetailCrm/Methods/V3/Statistic.php
index 66b5eb5..ed49eb2 100644
--- a/lib/RetailCrm/Methods/V3/Statistic.php
+++ b/lib/RetailCrm/Methods/V3/Statistic.php
@@ -40,7 +40,7 @@ trait Statistic
     {
         return $this->client->makeRequest(
             '/statistic/update',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 }
diff --git a/lib/RetailCrm/Methods/V3/Stores.php b/lib/RetailCrm/Methods/V3/Stores.php
index f35ab0b..8b9022b 100644
--- a/lib/RetailCrm/Methods/V3/Stores.php
+++ b/lib/RetailCrm/Methods/V3/Stores.php
@@ -56,7 +56,7 @@ trait Stores
 
         return $this->client->makeRequest(
             '/store/inventories',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -83,7 +83,7 @@ trait Stores
 
         return $this->client->makeRequest(
             '/store/inventories/upload',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['offers' => json_encode($offers)])
         );
     }
diff --git a/lib/RetailCrm/Methods/V3/Telephony.php b/lib/RetailCrm/Methods/V3/Telephony.php
index 77f0de4..8e0bbad 100644
--- a/lib/RetailCrm/Methods/V3/Telephony.php
+++ b/lib/RetailCrm/Methods/V3/Telephony.php
@@ -46,7 +46,7 @@ trait Telephony
 
         return $this->client->makeRequest(
             "/telephony/setting/$code",
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -95,7 +95,7 @@ trait Telephony
 
         return $this->client->makeRequest(
             '/telephony/call/event',
-            $this->client::METHOD_POST,
+            "POST",
             ['event' => json_encode($parameters)]
         );
     }
@@ -121,7 +121,7 @@ trait Telephony
 
         return $this->client->makeRequest(
             '/telephony/calls/upload',
-            $this->client::METHOD_POST,
+            "POST",
             ['calls' => json_encode($calls)]
         );
     }
@@ -149,7 +149,7 @@ trait Telephony
 
         return $this->client->makeRequest(
             '/telephony/manager',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/Customers.php b/lib/RetailCrm/Methods/V4/Customers.php
index 54087ef..0ccf28d 100644
--- a/lib/RetailCrm/Methods/V4/Customers.php
+++ b/lib/RetailCrm/Methods/V4/Customers.php
@@ -55,7 +55,7 @@ trait Customers
 
         return $this->client->makeRequest(
             '/customers/history',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/Delivery.php b/lib/RetailCrm/Methods/V4/Delivery.php
index d1a61a4..6c15a01 100644
--- a/lib/RetailCrm/Methods/V4/Delivery.php
+++ b/lib/RetailCrm/Methods/V4/Delivery.php
@@ -46,7 +46,7 @@ trait Delivery
 
         return $this->client->makeRequest(
             "/delivery/generic/setting/$code",
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -71,7 +71,7 @@ trait Delivery
 
         return $this->client->makeRequest(
             sprintf('/delivery/generic/setting/%s/edit', $configuration['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['configuration' => json_encode($configuration)]
         );
     }
@@ -102,7 +102,7 @@ trait Delivery
 
         return $this->client->makeRequest(
             sprintf('/delivery/generic/%s/tracking', $code),
-            $this->client::METHOD_POST,
+            "POST",
             ['statusUpdate' => json_encode($statusUpdate)]
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/Marketplace.php b/lib/RetailCrm/Methods/V4/Marketplace.php
index 68a6e01..d9fbab9 100644
--- a/lib/RetailCrm/Methods/V4/Marketplace.php
+++ b/lib/RetailCrm/Methods/V4/Marketplace.php
@@ -49,7 +49,7 @@ trait Marketplace
 
         return $this->client->makeRequest(
             sprintf('/marketplace/external/setting/%s/edit', $configuration['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['configuration' => json_encode($configuration)]
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/Orders.php b/lib/RetailCrm/Methods/V4/Orders.php
index 6ee8ff9..dc8bb80 100644
--- a/lib/RetailCrm/Methods/V4/Orders.php
+++ b/lib/RetailCrm/Methods/V4/Orders.php
@@ -61,7 +61,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -88,7 +88,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/create',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['order' => json_encode($order)])
         );
     }
@@ -114,7 +114,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/fix-external-ids',
-            $this->client::METHOD_POST,
+            "POST",
             ['orders' => json_encode($ids)
             ]
         );
@@ -145,7 +145,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/statuses',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -172,7 +172,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/upload',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['orders' => json_encode($orders)])
         );
     }
@@ -196,7 +196,7 @@ trait Orders
 
         return $this->client->makeRequest(
             "/orders/$id",
-            $this->client::METHOD_GET,
+            "GET",
             $this->fillSite($site, ['by' => $by])
         );
     }
@@ -232,7 +232,7 @@ trait Orders
 
         return $this->client->makeRequest(
             sprintf('/orders/%s/edit', $order[$by]),
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite(
                 $site,
                 ['order' => json_encode($order), 'by' => $by]
@@ -264,7 +264,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/history',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/References.php b/lib/RetailCrm/Methods/V4/References.php
index 24900ce..e40f454 100644
--- a/lib/RetailCrm/Methods/V4/References.php
+++ b/lib/RetailCrm/Methods/V4/References.php
@@ -43,7 +43,7 @@ trait References
     {
         return $this->client->makeRequest(
             '/reference/price-types',
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -74,7 +74,7 @@ trait References
 
         return $this->client->makeRequest(
             sprintf('/reference/price-types/%s/edit', $data['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['priceType' => json_encode($data)]
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/Stores.php b/lib/RetailCrm/Methods/V4/Stores.php
index cd64c8e..69e8515 100644
--- a/lib/RetailCrm/Methods/V4/Stores.php
+++ b/lib/RetailCrm/Methods/V4/Stores.php
@@ -51,7 +51,7 @@ trait Stores
 
         return $this->client->makeRequest(
             "/store/setting/$code",
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -76,7 +76,7 @@ trait Stores
 
         return $this->client->makeRequest(
             sprintf('/store/setting/%s/edit', $configuration['code']),
-            $this->client::METHOD_POST,
+            "POST",
             ['configuration' => json_encode($configuration)]
         );
     }
@@ -103,7 +103,7 @@ trait Stores
 
         return $this->client->makeRequest(
             '/store/prices/upload',
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite($site, ['prices' => json_encode($prices)])
         );
     }
@@ -137,7 +137,7 @@ trait Stores
 
         return $this->client->makeRequest(
             '/store/products',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/Telephony.php b/lib/RetailCrm/Methods/V4/Telephony.php
index 2082b5e..c9bac37 100644
--- a/lib/RetailCrm/Methods/V4/Telephony.php
+++ b/lib/RetailCrm/Methods/V4/Telephony.php
@@ -130,7 +130,7 @@ trait Telephony
 
         return $this->client->makeRequest(
             "/telephony/setting/$code/edit",
-            $this->client::METHOD_POST,
+            "POST",
             ['configuration' => json_encode($parameters)]
         );
     }
diff --git a/lib/RetailCrm/Methods/V4/Users.php b/lib/RetailCrm/Methods/V4/Users.php
index be45cc3..8f778cf 100644
--- a/lib/RetailCrm/Methods/V4/Users.php
+++ b/lib/RetailCrm/Methods/V4/Users.php
@@ -57,7 +57,7 @@ trait Users
         /** @noinspection PhpUndefinedMethodInspection */
         return $this->client->makeRequest(
             '/users',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -87,7 +87,7 @@ trait Users
         /** @noinspection PhpUndefinedMethodInspection */
         return $this->client->makeRequest(
             '/user-groups',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -106,6 +106,6 @@ trait Users
     public function usersGet($id)
     {
         /** @noinspection PhpUndefinedMethodInspection */
-        return $this->client->makeRequest("/users/$id", $this->client::METHOD_GET);
+        return $this->client->makeRequest("/users/$id", "GET");
     }
 }
diff --git a/lib/RetailCrm/Methods/V5/CustomFields.php b/lib/RetailCrm/Methods/V5/CustomFields.php
index 6e43d62..9e87ba7 100644
--- a/lib/RetailCrm/Methods/V5/CustomFields.php
+++ b/lib/RetailCrm/Methods/V5/CustomFields.php
@@ -52,7 +52,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             '/custom-fields',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -85,7 +85,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             "/custom-fields/$entity/create",
-            $this->client::METHOD_POST,
+            "POST",
             ['customField' => json_encode($customField)]
         );
     }
@@ -114,7 +114,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             "/custom-fields/$entity/edit/{$customField['code']}",
-            $this->client::METHOD_POST,
+            "POST",
             ['customField' => json_encode($customField)]
         );
     }
@@ -143,7 +143,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             "/custom-fields/$entity/$code",
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 
@@ -172,7 +172,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             '/custom-fields/dictionaries',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -197,7 +197,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             "/custom-fields/dictionaries/{$customDictionary['code']}/create",
-            $this->client::METHOD_POST,
+            "POST",
             ['customDictionary' => json_encode($customDictionary)]
         );
     }
@@ -222,7 +222,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             "/custom-fields/dictionaries/{$customDictionary['code']}/edit",
-            $this->client::METHOD_POST,
+            "POST",
             ['customDictionary' => json_encode($customDictionary)]
         );
     }
@@ -244,7 +244,7 @@ trait CustomFields
 
         return $this->client->makeRequest(
             "/custom-fields/dictionaries/$code",
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 }
diff --git a/lib/RetailCrm/Methods/V5/Customers.php b/lib/RetailCrm/Methods/V5/Customers.php
index 4b8e89e..b4a5fa5 100644
--- a/lib/RetailCrm/Methods/V5/Customers.php
+++ b/lib/RetailCrm/Methods/V5/Customers.php
@@ -50,7 +50,7 @@ trait Customers
 
         return $this->client->makeRequest(
             '/customers/combine',
-            $this->client::METHOD_POST,
+            "POST",
             [
                 'customers' => json_encode($customers),
                 'resultCustomer' => json_encode($resultCustomer)
diff --git a/lib/RetailCrm/Methods/V5/Orders.php b/lib/RetailCrm/Methods/V5/Orders.php
index efb6a74..3116310 100644
--- a/lib/RetailCrm/Methods/V5/Orders.php
+++ b/lib/RetailCrm/Methods/V5/Orders.php
@@ -59,7 +59,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/combine',
-            $this->client::METHOD_POST,
+            "POST",
             [
                 'technique' => $technique,
                 'order' => json_encode($order),
@@ -89,7 +89,7 @@ trait Orders
 
         return $this->client->makeRequest(
             '/orders/payments/create',
-            $this->client::METHOD_POST,
+            "POST",
             ['payment' => json_encode($payment)]
         );
     }
@@ -121,7 +121,7 @@ trait Orders
 
         return $this->client->makeRequest(
             sprintf('/orders/payments/%s/edit', $payment[$by]),
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite(
                 $site,
                 ['payment' => json_encode($payment), 'by' => $by]
diff --git a/lib/RetailCrm/Methods/V5/Segments.php b/lib/RetailCrm/Methods/V5/Segments.php
index ee3016b..260bdf5 100644
--- a/lib/RetailCrm/Methods/V5/Segments.php
+++ b/lib/RetailCrm/Methods/V5/Segments.php
@@ -52,7 +52,7 @@ trait Segments
 
         return $this->client->makeRequest(
             '/segments',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
diff --git a/lib/RetailCrm/Methods/V5/Stores.php b/lib/RetailCrm/Methods/V5/Stores.php
index ed21575..8100fca 100644
--- a/lib/RetailCrm/Methods/V5/Stores.php
+++ b/lib/RetailCrm/Methods/V5/Stores.php
@@ -60,7 +60,7 @@ trait Stores
 
         return $this->client->makeRequest(
             '/store/product-groups',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
diff --git a/lib/RetailCrm/Methods/V5/Tasks.php b/lib/RetailCrm/Methods/V5/Tasks.php
index 0f35ee4..5892e89 100644
--- a/lib/RetailCrm/Methods/V5/Tasks.php
+++ b/lib/RetailCrm/Methods/V5/Tasks.php
@@ -52,7 +52,7 @@ trait Tasks
 
         return $this->client->makeRequest(
             '/tasks',
-            $this->client::METHOD_GET,
+            "GET",
             $parameters
         );
     }
@@ -76,7 +76,7 @@ trait Tasks
 
         return $this->client->makeRequest(
             "/tasks/create",
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite(
                 $site,
                 ['task' => json_encode($task)]
@@ -103,7 +103,7 @@ trait Tasks
 
         return $this->client->makeRequest(
             "/tasks/{$task['id']}/edit",
-            $this->client::METHOD_POST,
+            "POST",
             $this->fillSite(
                 $site,
                 ['task' => json_encode($task)]
@@ -128,7 +128,7 @@ trait Tasks
 
         return $this->client->makeRequest(
             "/tasks/$id",
-            $this->client::METHOD_GET
+            "GET"
         );
     }
 }
diff --git a/lib/RetailCrm/Methods/V5/Users.php b/lib/RetailCrm/Methods/V5/Users.php
index 3454c8a..82b1331 100644
--- a/lib/RetailCrm/Methods/V5/Users.php
+++ b/lib/RetailCrm/Methods/V5/Users.php
@@ -53,7 +53,7 @@ trait Users
         /** @noinspection PhpUndefinedMethodInspection */
         return $this->client->makeRequest(
             "/users/$id/status",
-            $this->client::METHOD_POST,
+            "POST",
             ['status' => $status]
         );
     }