& & not copied (Moving av. price for material & would be negative)

What causes this issue?

Purchase order &V1&, item &V2& is not copied over to the document,
since posting this item would lead to a negative moving average price
for material &V3&.

System Response

The system does not permit a negative moving average price.

How to fix this error?

Check your entry in the field <LS>Amount</>.
If your entry was wrong, acknowledge the next message. From the
document overview screen choose <LS>Goto -> Open order item</>. A list
appears of items that were not copied over. At the end of the list you
will find purchase order &V1&, item &V2& and the amount you entered.
Correct this amount.
If the amount you entered was correct, take a look at:
the stock value of the material by choosing
( Environment -> Master data info -> Display material)
the posting history by choosing
(Environment -> Line items -> By material).
You may have to reverse postings that were made in the past (for
example, because goods receipts were wrongly valuated or price changes
were made wrongly) before you carry out the current posting.

Error message extract from SAP system. Copyright SAP SE.