diff --git a/Tanshu.Accounts.PointOfSale/Controllers/BillController.cs b/Tanshu.Accounts.PointOfSale/Controllers/BillController.cs
index 45f3184..530cf66 100644
--- a/Tanshu.Accounts.PointOfSale/Controllers/BillController.cs
+++ b/Tanshu.Accounts.PointOfSale/Controllers/BillController.cs
@@ -93,8 +93,8 @@ namespace Tanshu.Accounts.PointOfSale
                 quantity += item.inventory.Quantity;
             if (quantity < 0 && !Session.IsAllowed("Edit Printed Product"))
                 return;
-            var total = quantity + _bill.Where(x => x.Key.ProductID == key.ProductID && x.Key.KotID != Guid.Empty && x.Key.BillItemType == key.BillItemType).Sum(x => x.Value.inventory.Quantity);
-            quantity = Math.Max(quantity, 0);
+            var old = _bill.Where(x => x.Key.ProductID == key.ProductID && x.Key.KotID != Guid.Empty && x.Key.BillItemType == key.BillItemType).Sum(x => x.Value.inventory.Quantity);
+            quantity = Math.Max(quantity, -1 * old);
             item.inventory.Quantity = quantity;
         }
         public void SetPrice(BillItemValue item)
@@ -171,7 +171,7 @@ namespace Tanshu.Accounts.PointOfSale
 
         public bool CancelBillChanges()
         {
-            if (_bill.Any(x => x.Key.BillItemType != BillItemType.Kot) &&
+            if (_bill.Any(x => x.Key.BillItemType != BillItemType.Kot && x.Key.KotID == Guid.Empty) &&
                 MessageBox.Show("Abandon Changes?", "Abandon Changes", MessageBoxButtons.YesNo,
                                 MessageBoxIcon.Question, MessageBoxDefaultButton.Button2) == DialogResult.No)
                 return false;