diff --git a/backend/src/main/java/com/petshop/backend/repository/InventoryRepository.java b/backend/src/main/java/com/petshop/backend/repository/InventoryRepository.java
index 69ff16ed..b448b497 100644
--- a/backend/src/main/java/com/petshop/backend/repository/InventoryRepository.java
+++ b/backend/src/main/java/com/petshop/backend/repository/InventoryRepository.java
@@ -16,6 +16,9 @@ public interface InventoryRepository extends JpaRepository<Inventory, Long> {
     @Query("SELECT i FROM Inventory i WHERE i.product.prodId = :productId")
     Optional<Inventory> findByProductId(@Param("productId") Long productId);
 
+    @Query("SELECT i FROM Inventory i WHERE i.product.prodId = :productId AND i.store.storeId = :storeId")
+    Optional<Inventory> findByProductIdAndStoreId(@Param("productId") Long productId, @Param("storeId") Long storeId);
+
     @Query("SELECT i FROM Inventory i LEFT JOIN i.store s WHERE " +
            "LOWER(i.product.prodName) LIKE LOWER(CONCAT('%', :q, '%')) OR " +
            "LOWER(i.product.category.categoryName) LIKE LOWER(CONCAT('%', :q, '%')) OR " +
diff --git a/backend/src/main/java/com/petshop/backend/service/SaleService.java b/backend/src/main/java/com/petshop/backend/service/SaleService.java
index 643cfc2a..c90ad659 100644
--- a/backend/src/main/java/com/petshop/backend/service/SaleService.java
+++ b/backend/src/main/java/com/petshop/backend/service/SaleService.java
@@ -134,8 +134,8 @@ public class SaleService {
                             " for product: " + product.getProdName());
                 }
 
-                Inventory inventory = inventoryRepository.findByProductId(itemRequest.getProdId())
-                        .orElseThrow(() -> new ResourceNotFoundException("Inventory not found for product " + itemRequest.getProdId()));
+                Inventory inventory = inventoryRepository.findByProductIdAndStoreId(itemRequest.getProdId(), store.getStoreId())
+                        .orElseThrow(() -> new ResourceNotFoundException("Inventory not found for product " + itemRequest.getProdId() + " at store " + store.getStoreId()));
 
                 inventory.setQuantity(inventory.getQuantity() + itemRequest.getQuantity());
                 inventoryRepository.save(inventory);
@@ -158,8 +158,8 @@ public class SaleService {
                 Product product = productRepository.findById(itemRequest.getProdId())
                         .orElseThrow(() -> new ResourceNotFoundException("Product not found with id: " + itemRequest.getProdId()));
 
-                Inventory inventory = inventoryRepository.findByProductId(itemRequest.getProdId())
-                        .orElseThrow(() -> new ResourceNotFoundException("Inventory not found for product " + itemRequest.getProdId()));
+                Inventory inventory = inventoryRepository.findByProductIdAndStoreId(itemRequest.getProdId(), store.getStoreId())
+                        .orElseThrow(() -> new ResourceNotFoundException("Inventory not found for product " + itemRequest.getProdId() + " at store " + store.getStoreId()));
 
                 if (inventory.getQuantity() < itemRequest.getQuantity()) {
                     throw new BusinessException("Insufficient stock for product: " + product.getProdName() +
diff --git a/backend/src/main/resources/application.yml b/backend/src/main/resources/application.yml
index 5c79d7a6..07b2c86b 100644
--- a/backend/src/main/resources/application.yml
+++ b/backend/src/main/resources/application.yml
@@ -9,7 +9,7 @@ spring:
       max-request-size: 5MB
 
   datasource:
-    url: ${SPRING_DATASOURCE_URL:jdbc:mysql://localhost:3307/Petstoredb_target?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC}
+    url: ${SPRING_DATASOURCE_URL:jdbc:mysql://localhost:3306/Petstoredb?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC}
     username: ${SPRING_DATASOURCE_USERNAME:petshop}
     password: ${SPRING_DATASOURCE_PASSWORD:petshop}
     driver-class-name: com.mysql.cj.jdbc.Driver