While you are trying to cancel a document that increases the stock of a product, you may receive the following message:
"Negative stock is not supported. Availability is not updated."
The reason is, you are canceling a document [Purchase Bill/Goods In/Receive on Consignment] that brought in stock which was then shipped/sold.
If you were allowed to cancel this, you would end up with negative stock at some point in history for the items listed in the warning message.
Consider the following example:
Now, if Purchase Bill #1 is cancelled, then, SKU XYZ01 will present a quantity of minus five (-5) on the 20th of March after the issue of Sales Invoice #1:
In such cases, to be able to cancel Purchase Bill #1 there are two workarounds:
Issue a new "correction" Purchase Bill that includes SKU: XYZ01 and when approving it, backdate it for the 10th of March. The quantity of SKU: XYZ01 in this correction purchase bill should be at least 7 to match with the quantity sold later.
Cancel Purchase Bill #1
Cancel all the documents that sold/shipped the SKU: XYZ01 after Purchase Bill #1. In this case, Sales Invoices #1 and #2 should be cancelled first.
Cancel Purchase Bill #1.
Or login to your account.