Someone or something is closing lines and documents in POP! This makes it impossible to match the invoice to the receipt.
There is no automatic closing of the PO lines. IF a line is received exactly (ie you order 10 and receive 10, it is marked complete but not closed. The PO never gets automatically closed unless everything is received at exactly 100% of the order and is matched to an invoice exactly with no variances. ANY alteration (order 10, receive 9 or receive 11, or invoice for a different unit cost) and the documents are left open to be manually closed.
Check in your firm (especially the purchasing department) to see if they are closing the POs. If you are running MRP or some other planing product, open POs are seen as a planned delivery and need to be closed. Some purchasing people do not realize that this cannot occur until the receipt is matched to an invoice. An alternative solution for the outstanding quantities for the purchasing team is to cancel any outstanding un-received quantities that will not be shipped. This leaves the document/lines open to be matched.
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