diff --git a/.travis.yml b/.travis.yml
index f828c00..f48df70 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,6 +19,7 @@ env:
 
 stages:
   - test
+  - phpcs
   - deploy
 
 before_install:
@@ -119,6 +120,10 @@ jobs:
       env: TEST_SUITE=3.0 OPENCART=3.0.3.1
     - php: 7.3
       env: TEST_SUITE=3.0 OPENCART=3.0.3.2
+    - stage: phpcs
+      before_script: composer install
+      script: make phpcomp
+      after_success: skip
     - stage: deploy
       before_script: skip
       script: make build_archive
diff --git a/Makefile b/Makefile
index 4bf3481..d0eb813 100644
--- a/Makefile
+++ b/Makefile
@@ -45,3 +45,9 @@ run_test: run
 
 test: robo_deploy
 	composer test
+
+phpcs-config:
+	bin/phpcs --config-set installed_paths vendor/phpcompatibility/php-compatibility
+
+phpcomp: phpcs-config
+	@bin/phpcs -s -p ./src --standard=PHPCompatibility --runtime-set testVersion 5.4-7.3
diff --git a/VERSION b/VERSION
index 4d0dcda..de197cc 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.1.2
+4.1.3
diff --git a/composer.json b/composer.json
index 581e825..a85205b 100644
--- a/composer.json
+++ b/composer.json
@@ -32,7 +32,6 @@
     },
     "require-dev": {
       "consolidation/robo": "~1.0",
-        "beyondit/opencart-test-suite": "~3.0",
-        "opencart/opencart": "3.0.2.0"
+      "phpcompatibility/php-compatibility": "^9.3"
     }
 }
diff --git a/src/upload/admin/controller/extension/module/retailcrm.php b/src/upload/admin/controller/extension/module/retailcrm.php
index 5b2e177..5511cb7 100644
--- a/src/upload/admin/controller/extension/module/retailcrm.php
+++ b/src/upload/admin/controller/extension/module/retailcrm.php
@@ -278,7 +278,6 @@ class ControllerExtensionModuleRetailcrm extends Controller
             'button_cancel',
             'text_notice',
             'retailcrm_title',
-            'retailcrm_apiversion',
             'retailcrm_url',
             'retailcrm_apikey',
             'retailcrm_base_settings',
@@ -358,9 +357,6 @@ class ControllerExtensionModuleRetailcrm extends Controller
         $key = isset($_data['saved_settings'][$this->moduleTitle . '_apikey'])
             ? $_data['saved_settings'][$this->moduleTitle . '_apikey']
             : null;
-        $apiVersion = isset($_data['saved_settings'][$this->moduleTitle . '_apiversion'])
-            ? $_data['saved_settings'][$this->moduleTitle . '_apiversion']
-            : null;
 
         if (!empty($url) && !empty($key)) {
 
@@ -370,11 +366,8 @@ class ControllerExtensionModuleRetailcrm extends Controller
                 ->getOrderStatuses();
             $_data['payments'] = $this->model_extension_retailcrm_references
                 ->getPaymentTypes();
-
-            if ($apiVersion == 'v5') {
-                $_data['customFields'] = $this->model_extension_retailcrm_references
-                    ->getCustomFields();
-            }
+            $_data['customFields'] = $this->model_extension_retailcrm_references
+                ->getCustomFields();
 
             $_data['lenghts'] = $this->model_localisation_length_class->getLengthClasses();
             $_data['priceTypes'] = $this->model_extension_retailcrm_references
diff --git a/src/upload/admin/language/en-gb/extension/module/retailcrm.php b/src/upload/admin/language/en-gb/extension/module/retailcrm.php
index c7036d2..81d7ded 100644
--- a/src/upload/admin/language/en-gb/extension/module/retailcrm.php
+++ b/src/upload/admin/language/en-gb/extension/module/retailcrm.php
@@ -20,7 +20,6 @@ $_['collector_tab_text']         = 'Daemon Collector';
 $_['logs_tab_text']              = 'Logs';
 $_['collector_custom_text']      = 'Configuration of form fields';
 $_['custom_fields_tab_text']     = 'Custom fields';
-$_['retailcrm_apiversion']       = 'API Version';
 $_['retailcrm_url']              = 'URL of retailCRM';
 $_['retailcrm_apikey']           = 'API key of retailCRM';
 $_['corporate_enabled_label']    = 'Corporate customers support';
diff --git a/src/upload/admin/language/es-es/extension/module/retailcrm.php b/src/upload/admin/language/es-es/extension/module/retailcrm.php
index a13bfd3..af4f9ce 100644
--- a/src/upload/admin/language/es-es/extension/module/retailcrm.php
+++ b/src/upload/admin/language/es-es/extension/module/retailcrm.php
@@ -20,7 +20,6 @@ $_['collector_tab_text']         = 'Daemon Collector';
 $_['logs_tab_text']              = 'Registro';
 $_['collector_custom_text']      = 'Configurar campos de formulario';
 $_['custom_fields_tab_text']     = 'Campos personalizados';
-$_['retailcrm_apiversion']       = 'Versión de la API';
 $_['retailcrm_url']              = 'Dirección del retailCRM';
 $_['retailcrm_apikey']           = 'Clave de la API del retailCRM';
 $_['corporate_enabled_label']    = 'Corporate customers support';
diff --git a/src/upload/admin/language/ru-ru/extension/module/retailcrm.php b/src/upload/admin/language/ru-ru/extension/module/retailcrm.php
index 446afda..24ada07 100644
--- a/src/upload/admin/language/ru-ru/extension/module/retailcrm.php
+++ b/src/upload/admin/language/ru-ru/extension/module/retailcrm.php
@@ -20,7 +20,6 @@ $_['consultant_tab_text']         = 'Online Consultant';
 $_['logs_tab_text']              = 'Логи';
 $_['collector_custom_text']      = 'Настройка полей формы';
 $_['custom_fields_tab_text']     = 'Пользовательские поля';
-$_['retailcrm_apiversion']       = 'Версия API';
 $_['retailcrm_url']              = 'Адрес RetailCRM';
 $_['retailcrm_apikey']           = 'Api ключ RetailCRM';
 $_['corporate_enabled_label']    = 'Поддержка корпоративных клиентов';
diff --git a/src/upload/admin/model/extension/retailcrm/prices.php b/src/upload/admin/model/extension/retailcrm/prices.php
index 1f19995..6a929f1 100644
--- a/src/upload/admin/model/extension/retailcrm/prices.php
+++ b/src/upload/admin/model/extension/retailcrm/prices.php
@@ -60,10 +60,6 @@ class ModelExtensionRetailcrmPrices extends Model
         $prices = array();
         $site = $this->getSite($retailcrmApiClient);
 
-        if ($this->settings[$this->moduleTitle . '_apiversion'] == 'v3') {
-            return false;
-        }
-
         foreach ($products as $product) {
             $specials = $this->model_catalog_product->getProductSpecials($product['product_id']);
 
diff --git a/src/upload/catalog/model/extension/retailcrm/order.php b/src/upload/catalog/model/extension/retailcrm/order.php
index c208388..790a203 100644
--- a/src/upload/catalog/model/extension/retailcrm/order.php
+++ b/src/upload/catalog/model/extension/retailcrm/order.php
@@ -68,7 +68,7 @@ class ModelExtensionRetailcrmOrder extends Model {
                 $response = $retailcrmApiClient->ordersEdit($order);
             }
 
-            if ($this->settings[$this->moduleTitle . '_apiversion'] == 'v5' && $response->isSuccessful()) {
+            if ($response->isSuccessful()) {
                 $this->updatePayment($order_payment, $order['externalId'], $retailcrmApiClient);
             }
         }
@@ -169,16 +169,8 @@ class ModelExtensionRetailcrmOrder extends Model {
         }
 
         $order['createdAt'] = $order_data['date_added'];
-
-        if ($this->settings[$this->moduleTitle . '_apiversion'] != 'v5') {
-            $order['paymentType'] = $payment_code;
-            if ($couponTotal > 0) {
-                $order['discount'] = $couponTotal;
-            }
-        } else {
-            if ($couponTotal > 0) {
-                $order['discountManualAmount'] = $couponTotal;
-            }
+        if ($couponTotal > 0) {
+            $order['discountManualAmount'] = $couponTotal;
         }
 
         $country = isset($order_data['shipping_country']) ? $order_data['shipping_country'] : '' ;
@@ -245,38 +237,29 @@ class ModelExtensionRetailcrmOrder extends Model {
                 $offerId = implode('_', $offerId);
             }
 
-            if ($this->settings[$this->moduleTitle . '_apiversion'] != 'v3') {
-                $item = array(
-                    'offer' => array(
-                        'externalId' => !empty($offerId) ? $product['product_id'].'#'.$offerId : $product['product_id']
-                    ),
-                    'productName' => $product['name'],
-                    'initialPrice' => $product['price'],
-                    'quantity' => $product['quantity']
-                );
+            $item = array(
+                'offer' => array(
+                    'externalId' => !empty($offerId) ? $product['product_id'].'#'.$offerId : $product['product_id']
+                ),
+                'productName' => $product['name'],
+                'initialPrice' => $product['price'],
+                'quantity' => $product['quantity']
+            );
 
-                $specials = $this->model_extension_retailcrm_product->getProductSpecials($product['product_id']);
+            $specials = $this->model_extension_retailcrm_product->getProductSpecials($product['product_id']);
 
-                if (!empty($specials)) {
-                    $customer = $this->model_account_customer->getCustomer($order_data['customer_id']);
+            if (!empty($specials)) {
+                $customer = $this->model_account_customer->getCustomer($order_data['customer_id']);
 
-                    foreach ($specials as $special) {
-                        if (isset($customer['customer_group_id'])) {
-                            if ($special['customer_group_id'] == $customer['customer_group_id']) {
-                                if ($this->settings[$this->moduleTitle . '_special_' . $customer['customer_group_id']]) {
-                                    $item['priceType']['code'] = $this->settings[$this->moduleTitle . '_special_' . $customer['customer_group_id']];
-                                }
+                foreach ($specials as $special) {
+                    if (isset($customer['customer_group_id'])) {
+                        if ($special['customer_group_id'] == $customer['customer_group_id']) {
+                            if ($this->settings[$this->moduleTitle . '_special_' . $customer['customer_group_id']]) {
+                                $item['priceType']['code'] = $this->settings[$this->moduleTitle . '_special_' . $customer['customer_group_id']];
                             }
                         }
                     }
                 }
-            } else {
-                $item = array(
-                    'productName' => $product['name'],
-                    'initialPrice' => $product['price'],
-                    'quantity' => $product['quantity'],
-                    'productId' => !empty($offerId) ? $product['product_id'].'#'.$offerId : $product['product_id']
-                );
             }
 
             if (isset($properties)) $item['properties'] = $properties;
diff --git a/src/upload/system/library/retailcrm/lib/api/CurlException.php b/src/upload/system/library/retailcrm/lib/api/CurlException.php
index dbc5868..8eab88c 100644
--- a/src/upload/system/library/retailcrm/lib/api/CurlException.php
+++ b/src/upload/system/library/retailcrm/lib/api/CurlException.php
@@ -8,7 +8,7 @@
  * @package  RetailCrm
  * @author   RetailCrm <integration@retailcrm.ru>
  * @license  https://opensource.org/licenses/MIT MIT License
- * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion4
+ * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion5
  */
 class CurlException extends RuntimeException
 {
diff --git a/src/upload/system/library/retailcrm/lib/api/InvalidJsonException.php b/src/upload/system/library/retailcrm/lib/api/InvalidJsonException.php
index 1e631c2..c35e419 100644
--- a/src/upload/system/library/retailcrm/lib/api/InvalidJsonException.php
+++ b/src/upload/system/library/retailcrm/lib/api/InvalidJsonException.php
@@ -8,7 +8,7 @@
  * @package  RetailCrm
  * @author   RetailCrm <integration@retailcrm.ru>
  * @license  https://opensource.org/licenses/MIT MIT License
- * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion4
+ * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion5
  */
 class InvalidJsonException extends DomainException
 {
diff --git a/src/upload/system/library/retailcrm/lib/api/RetailcrmApiResponse.php b/src/upload/system/library/retailcrm/lib/api/RetailcrmApiResponse.php
index b63599f..24f3080 100644
--- a/src/upload/system/library/retailcrm/lib/api/RetailcrmApiResponse.php
+++ b/src/upload/system/library/retailcrm/lib/api/RetailcrmApiResponse.php
@@ -8,7 +8,7 @@
  * @package  RetailCrm
  * @author   RetailCrm <integration@retailcrm.ru>
  * @license  https://opensource.org/licenses/MIT MIT License
- * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion4
+ * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion5
  */
 class RetailcrmApiResponse implements ArrayAccess
 {
diff --git a/src/upload/system/library/retailcrm/lib/api/RetailcrmHttpClient.php b/src/upload/system/library/retailcrm/lib/api/RetailcrmHttpClient.php
index 7f4d4e0..4294d97 100644
--- a/src/upload/system/library/retailcrm/lib/api/RetailcrmHttpClient.php
+++ b/src/upload/system/library/retailcrm/lib/api/RetailcrmHttpClient.php
@@ -8,7 +8,7 @@
  * @package  RetailCrm
  * @author   RetailCrm <integration@retailcrm.ru>
  * @license  https://opensource.org/licenses/MIT MIT License
- * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion4
+ * @link     http://www.retailcrm.ru/docs/Developers/ApiVersion5
  */
 class RetailcrmHttpClient
 {
diff --git a/src/upload/system/library/retailcrm/lib/history/Order.php b/src/upload/system/library/retailcrm/lib/history/Order.php
index b7d3f4b..5cc44be 100644
--- a/src/upload/system/library/retailcrm/lib/history/Order.php
+++ b/src/upload/system/library/retailcrm/lib/history/Order.php
@@ -229,7 +229,7 @@ class Order {
             $product_id = $item['offer']['externalId'];
             $options = array();
 
-            if (mb_strpos($item['offer']['externalId'], '#') > 1) {
+            if (mb_strpos($item['offer']['externalId'], '#', 0, mb_internal_encoding()) > 1) {
                 $offer = explode('#', $item['offer']['externalId']);
                 $product_id = $offer[0];
                 $options_from_crm = explode('_', $offer[1]);
diff --git a/src/upload/system/library/retailcrm/lib/service/SettingsManager.php b/src/upload/system/library/retailcrm/lib/service/SettingsManager.php
index 962d975..e3b8243 100644
--- a/src/upload/system/library/retailcrm/lib/service/SettingsManager.php
+++ b/src/upload/system/library/retailcrm/lib/service/SettingsManager.php
@@ -18,8 +18,10 @@ class SettingsManager extends \retailcrm\Base {
     }
 
     public function getSetting($key) {
-        if (!empty($this->getSettings()[$this->retailcrm->getModuleTitle() . '_' . $key])) {
-            return $this->getSettings()[$this->retailcrm->getModuleTitle() . '_' . $key];
+        $settings = $this->getSettings();
+
+        if (!empty($settings[$this->retailcrm->getModuleTitle() . '_' . $key])) {
+            return $settings[$this->retailcrm->getModuleTitle() . '_' . $key];
         }
 
         return null;
diff --git a/src/upload/system/library/retailcrm/retailcrm.php b/src/upload/system/library/retailcrm/retailcrm.php
index f9930e2..c6e4ab8 100644
--- a/src/upload/system/library/retailcrm/retailcrm.php
+++ b/src/upload/system/library/retailcrm/retailcrm.php
@@ -52,11 +52,10 @@ class Retailcrm {
      *
      * @param string $apiUrl (default = null)
      * @param string $apiKey (default = null)
-     * @param string $apiVersion (default = null)
      *
      * @return mixed object | boolean
      */
-    public function getApiClient($apiUrl = null, $apiKey = null, $apiVersion = null) {
+    public function getApiClient($apiUrl = null, $apiKey = null) {
         if (!$this->registry->has('RetailcrmProxy')) {
             $setting = $this->model_setting_setting->getSetting($this->getModuleTitle());