You will need to remove the GL Lock Date Set and Move to Return | Create Credit Slip | Post to Payable as normal. Then add the GL Lock Date again to keep other entries from posting prior to that date.
NOTE: There will be an impact on the following accounts and the closed period as follows:
- Credit to the Parts Received for Work In Progress
- Debit to the Returned Items
- Debit to the Parts Received for Work In Progress
- Credit the Returned Items