diff --git a/src/controllers/cart.js b/src/controllers/cart.js
index a6acb95..951402b 100644
--- a/src/controllers/cart.js
+++ b/src/controllers/cart.js
@@ -79,9 +79,9 @@ export const addNewCart = ({ userId, products = [] }) => {
   let totalQuantity = 0;
 
   // get products in the relevant schema
-  const someProducts = productsByIds.map((p, idx) => {
-    // get quantity of the product
-    const quantity = productQty[idx];
+  const someProducts = productsByIds.map((p) => {
+    const originalIndex = productIds.indexOf(p.id); // match by id
+    const quantity = productQty[originalIndex];
 
     // total price (price * quantity)
     const priceWithQty = p.price * quantity;
@@ -219,4 +219,4 @@ export const deleteCartById = ({ id }) => {
   cart.deletedOn = new Date().toISOString();
 
   return cart;
-};
+};
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