diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index fbde9456..2cdc68ab 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -72,7 +72,7 @@ Code Coverage:
 SW 5.2:
     stage: Shopware Versions
     needs: [PHP analyze]
-    image: shopware/5-continuous:7.1
+    image: shopware/5-continuous:5.6
     before_script: []
     variables:
         CHECKOUT_SHOPWARE_BRANCH: "5.2"
diff --git a/Components/Backend/VoidService.php b/Components/Backend/VoidService.php
index 389bde37..01bd66b9 100644
--- a/Components/Backend/VoidService.php
+++ b/Components/Backend/VoidService.php
@@ -1,4 +1,4 @@
-<?php declare(strict_types=1);
+<?php
 /**
  * (c) shopware AG <info@shopware.com>
  *
diff --git a/Tests/Functional/Components/Backend/PaymentDetailsServiceTest.php b/Tests/Functional/Components/Backend/PaymentDetailsServiceTest.php
index b8ea0aaa..57d4bfdc 100644
--- a/Tests/Functional/Components/Backend/PaymentDetailsServiceTest.php
+++ b/Tests/Functional/Components/Backend/PaymentDetailsServiceTest.php
@@ -28,7 +28,7 @@ class PaymentDetailsServiceTest extends TestCase
     const SALE_ID = 'saleId';
     const LEGACY_ID = 'legacyId';
 
-    public function testGetPaymentDetailsOrder(): void
+    public function testGetPaymentDetailsOrder()
     {
         $result = $this->createPaymentDetailService()->getPaymentDetails(self::ORDER_ID, '0', '');
 
@@ -38,7 +38,7 @@ public function testGetPaymentDetailsOrder(): void
         static::assertArrayHasKey('history', $result);
     }
 
-    public function testGetPaymentDetailsAuthorization(): void
+    public function testGetPaymentDetailsAuthorization()
     {
         $result = $this->createPaymentDetailService()->getPaymentDetails(self::AUTHORIZATION_ID, '0', '');
 
@@ -48,7 +48,7 @@ public function testGetPaymentDetailsAuthorization(): void
         static::assertArrayHasKey('history', $result);
     }
 
-    public function testGetPaymentDetailsSale(): void
+    public function testGetPaymentDetailsSale()
     {
         $result = $this->createPaymentDetailService()->getPaymentDetails(self::SALE_ID, '0', '');
 
@@ -58,7 +58,7 @@ public function testGetPaymentDetailsSale(): void
         static::assertArrayHasKey('history', $result);
     }
 
-    public function testGetPaymentDetailsSaleThrowException(): void
+    public function testGetPaymentDetailsSaleThrowException()
     {
         $result = $this->createPaymentDetailService()->getPaymentDetails(PaymentResourceMock::THROW_EXCEPTION, '0', '');
 
@@ -69,7 +69,7 @@ public function testGetPaymentDetailsSaleThrowException(): void
         static::assertArrayNotHasKey('history', $result);
     }
 
-    public function testGetPaymentDetailsLegacy(): void
+    public function testGetPaymentDetailsLegacy()
     {
         $legacyPaymentId = '99';
         /** @var Connection $connection */
diff --git a/Tests/Functional/Components/Backend/VoidServiceTest.php b/Tests/Functional/Components/Backend/VoidServiceTest.php
index bbd69afb..c2711a0b 100644
--- a/Tests/Functional/Components/Backend/VoidServiceTest.php
+++ b/Tests/Functional/Components/Backend/VoidServiceTest.php
@@ -31,7 +31,7 @@ protected function setUp()
         $this->modelManager = Shopware()->Container()->get('models');
     }
 
-    public function testVoidOrder(): void
+    public function testVoidOrder()
     {
         $orderId = $this->createOrder(OrderResourceMock::PAYPAL_PAYMENT_ID);
 
@@ -43,7 +43,7 @@ public function testVoidOrder(): void
         static::assertTrue($result['success']);
     }
 
-    public function testVoidOrderThrowException(): void
+    public function testVoidOrderThrowException()
     {
         $orderId = $this->createOrder(OrderResourceMock::PAYPAL_PAYMENT_ID);
 
@@ -55,7 +55,7 @@ public function testVoidOrderThrowException(): void
         static::assertFalse($result['success']);
     }
 
-    public function testVoidAuthorization(): void
+    public function testVoidAuthorization()
     {
         $orderId = $this->createOrder(AuthorizationResourceMock::PAYPAL_PAYMENT_ID);
 
@@ -67,7 +67,7 @@ public function testVoidAuthorization(): void
         static::assertTrue($result['success']);
     }
 
-    public function testVoidAuthorizationThrowException(): void
+    public function testVoidAuthorizationThrowException()
     {
         $orderId = $this->createOrder(AuthorizationResourceMock::PAYPAL_PAYMENT_ID);