diff --git a/vendor/magento/module-quote-graph-ql/Model/Cart/AddProductsToCart.php b/vendor/magento/module-quote-graph-ql/Model/Cart/AddProductsToCart.php
index 0360d9ccf54..86cbb839d34 100644
--- a/vendor/magento/module-quote-graph-ql/Model/Cart/AddProductsToCart.php
+++ b/vendor/magento/module-quote-graph-ql/Model/Cart/AddProductsToCart.php
@@ -8,7 +8,6 @@ declare(strict_types=1);
 namespace Magento\QuoteGraphQl\Model\Cart;

 use Magento\Framework\GraphQl\Exception\GraphQlInputException;
-use Magento\Framework\Message\MessageInterface;
 use Magento\Quote\Api\CartRepositoryInterface;
 use Magento\Quote\Model\Quote;

@@ -53,7 +52,6 @@ class AddProductsToCart
         foreach ($cartItems as $cartItemData) {
             $this->addProductToCart->execute($cart, $cartItemData);
         }
-
         $this->cartRepository->save($cart);
     }
 }
diff --git a/vendor/magento/module-quote-graph-ql/Model/Resolver/AddSimpleProductsToCart.php b/vendor/magento/module-quote-graph-ql/Model/Resolver/AddSimpleProductsToCart.php
index 2135f3798d1..0adfbcc1d18 100644
--- a/vendor/magento/module-quote-graph-ql/Model/Resolver/AddSimpleProductsToCart.php
+++ b/vendor/magento/module-quote-graph-ql/Model/Resolver/AddSimpleProductsToCart.php
@@ -13,6 +13,7 @@ use Magento\Framework\GraphQl\Query\ResolverInterface;
 use Magento\Framework\GraphQl\Schema\Type\ResolveInfo;
 use Magento\QuoteGraphQl\Model\Cart\AddProductsToCart;
 use Magento\QuoteGraphQl\Model\Cart\GetCartForUser;
+use Magento\Framework\Lock\LockManagerInterface;

 /**
  * Add simple products to cart GraphQl resolver
@@ -30,16 +31,24 @@ class AddSimpleProductsToCart implements ResolverInterface
      */
     private $addProductsToCart;

+    /**
+     * @var LockManagerInterface
+     */
+    private $lockManager;
+
     /**
      * @param GetCartForUser $getCartForUser
      * @param AddProductsToCart $addProductsToCart
+     * @param LockManagerInterface $lockManager
      */
     public function __construct(
         GetCartForUser $getCartForUser,
-        AddProductsToCart $addProductsToCart
+        AddProductsToCart $addProductsToCart,
+        LockManagerInterface $lockManager
     ) {
         $this->getCartForUser = $getCartForUser;
         $this->addProductsToCart = $addProductsToCart;
+        $this->lockManager = $lockManager;
     }

     /**
@@ -58,12 +67,20 @@ class AddSimpleProductsToCart implements ResolverInterface
             throw new GraphQlInputException(__('Required parameter "cart_items" is missing'));
         }
         $cartItems = $args['input']['cart_items'];
-
         $storeId = (int)$context->getExtensionAttributes()->getStore()->getId();
+
+        $lockName = 'cart_processing_lock_' . $maskedCartId;
+        while ($this->lockManager->isLocked($lockName)) {
+            // wait till other process working with the same cart complete
+            usleep(rand(100, 600));
+        }
+        $this->lockManager->lock($lockName, 1);
+
         $cart = $this->getCartForUser->execute($maskedCartId, $context->getUserId(), $storeId);
         $this->addProductsToCart->execute($cart, $cartItems);
-
         $cart = $this->getCartForUser->execute($maskedCartId, $context->getUserId(), $storeId);
+
+        $this->lockManager->unlock($lockName);
         return [
             'cart' => [
                 'model' => $cart,