diff --git a/code/20 Advanced Redux/02-refresher-practice-finished/src/store/cart-slice.js b/code/20 Advanced Redux/02-refresher-practice-finished/src/store/cart-slice.js
index dce632d86..1d26d83aa 100644
--- a/code/20 Advanced Redux/02-refresher-practice-finished/src/store/cart-slice.js	
+++ b/code/20 Advanced Redux/02-refresher-practice-finished/src/store/cart-slice.js	
@@ -32,6 +32,7 @@ const cartSlice = createSlice({
         state.items = state.items.filter(item => item.id !== id);
       } else {
         existingItem.quantity--;
+        existingItem.totalPrice = existingItem.totalPrice - newItem.price;
       }
     },
   },