May be the packing slip is locked by axapta due to axapta down or sudden closure of axapta client. Use the below query to find out the lines based on the packing slip and delete them. Later, invoice the packing slip.
select
from [PURCHPARMSUBLINE] where documentid in (select packingslipid from vendpackingslipjour
You can disable the picking requirments from the item’s Inventory model group , however if you want the picking to be mandatory then i think the issue is with registering the picking list as not all the quantities are being updates or if you any associated output orders related check the inventory inquiries on the salesline level for this.
The net quantity of the purchase invoice must be negative - this means you are creating a credit, it is the only real explanation for the presentation of the picking list restriction. Ziad is correct that unchecking this would resolve your issue, but you need to understand it first. Why is it asking for picked lines when you are processing a purchase invoice?
The main cause that is PO changed status =Received, and have 2 lines in Purchase order line, one is positive, one is negotive ( was make credit note).
The PO then correct process, but it depend on ITEM ID that we need to posting, I think that have problem with quantity of this item on hand and quantity on PO.