diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/ChangeCustomerPasswordTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/ChangeCustomerPasswordTest.php
index f36200c8e921..bf01ad4b3721 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/ChangeCustomerPasswordTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/ChangeCustomerPasswordTest.php
@@ -48,7 +48,7 @@ class ChangeCustomerPasswordTest extends GraphQlAbstract
      */
     private $customerRepository;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         $this->customerTokenService = Bootstrap::getObjectManager()->get(CustomerTokenServiceInterface::class);
         $this->accountManagement = Bootstrap::getObjectManager()->get(AccountManagementInterface::class);
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerAddressTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerAddressTest.php
index 408a254f65f2..573b30e79c10 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerAddressTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerAddressTest.php
@@ -29,7 +29,7 @@ class CreateCustomerAddressTest extends GraphQlAbstract
      */
     private $addressRepository;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerTest.php
index 0be968d6d340..5846880c6ee2 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/CreateCustomerTest.php
@@ -13,7 +13,7 @@
 use Magento\TestFramework\TestCase\GraphQlAbstract;
 
 /**
- * Test for create customer functionallity
+ * Test for create customer functionality
  */
 class CreateCustomerTest extends GraphQlAbstract
 {
@@ -27,7 +27,7 @@ class CreateCustomerTest extends GraphQlAbstract
      */
     private $customerRepository;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
@@ -308,7 +308,7 @@ public function testCreateCustomerSubscribed()
         $this->assertEquals(false, $response['createCustomer']['customer']['is_subscribed']);
     }
 
-    public function tearDown()
+    public function tearDown(): void
     {
         $newEmail = 'new_customer@example.com';
         try {
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/DeleteCustomerAddressTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/DeleteCustomerAddressTest.php
index 443b9d7ec53e..31065f3f6f98 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/DeleteCustomerAddressTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/DeleteCustomerAddressTest.php
@@ -39,7 +39,7 @@ class DeleteCustomerAddressTest extends GraphQlAbstract
      */
     private $lockCustomer;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetAddressesTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetAddressesTest.php
index c1573d7dbd8a..ed360919d832 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetAddressesTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetAddressesTest.php
@@ -31,7 +31,7 @@ class GetAddressesTest extends GraphQlAbstract
      */
     private $lockCustomer;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetCustomerTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetCustomerTest.php
index 56e950c45fae..c645d8953981 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetCustomerTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/GetCustomerTest.php
@@ -36,7 +36,7 @@ class GetCustomerTest extends GraphQlAbstract
      */
     private $customerRepository;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/SubscriptionStatusTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/SubscriptionStatusTest.php
index bbb7e245c91f..4cba8323793d 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/SubscriptionStatusTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/SubscriptionStatusTest.php
@@ -29,7 +29,7 @@ class SubscriptionStatusTest extends GraphQlAbstract
      */
     private $subscriberFactory;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
@@ -162,7 +162,7 @@ private function getHeaderMap(string $email, string $password): array
         return ['Authorization' => 'Bearer ' . $customerToken];
     }
 
-    protected function tearDown()
+    protected function tearDown(): void
     {
         parent::tearDown();
 
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerAddressTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerAddressTest.php
index 60f1f2d64df9..da6790099494 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerAddressTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerAddressTest.php
@@ -40,7 +40,7 @@ class UpdateCustomerAddressTest extends GraphQlAbstract
      */
     private $lockCustomer;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerTest.php
index d1c6638e8d5f..7121f12bc2a4 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Customer/UpdateCustomerTest.php
@@ -33,7 +33,7 @@ class UpdateCustomerTest extends GraphQlAbstract
      */
     private $lockCustomer;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
diff --git a/dev/tests/api-functional/testsuite/Magento/GraphQl/Quote/Customer/AddSimpleProductToCartTest.php b/dev/tests/api-functional/testsuite/Magento/GraphQl/Quote/Customer/AddSimpleProductToCartTest.php
index f7ba5b4d924f..121eb6aff44b 100644
--- a/dev/tests/api-functional/testsuite/Magento/GraphQl/Quote/Customer/AddSimpleProductToCartTest.php
+++ b/dev/tests/api-functional/testsuite/Magento/GraphQl/Quote/Customer/AddSimpleProductToCartTest.php
@@ -29,7 +29,7 @@ class AddSimpleProductToCartTest extends GraphQlAbstract
      */
     private $getMaskedQuoteIdByReservedOrderId;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         $objectManager = Bootstrap::getObjectManager();
         $this->customerTokenService = $objectManager->get(CustomerTokenServiceInterface::class);