Hi Miller,
If my understanding is correct, following are the process you have made in the GP system,
1. Created PO for item XXX
2. Posted Received transaction entry for XXX item.
3. Made Enter/Match Invoice and posted for that PO
4. Realized XXX item not received
5. Created Return entry and posted
6. now, need to receive the same item again.
If so,
Solution: You can create a new PO and receive the item again.
Please update if my understanding is wrong.