What is the best way to close a PO that is paid without a 2-way voucher match?

We have just started using Non-Stock Purchase Orders and several of the items ordered have been paid without using P4314 2-way match. The PO shows still open (status 380) but the item ordered has been invoiced and paid. There is no financial encumbrance and without having to void the check and the voucher, what can be done to close the PO? In another month we will convert all equipment, supplies, and contracted purchases to Non-Stock Purchase Orders so 2 Way Matching will become more used than Expense Vouchering (P04105).