You can use pending returns only for items on an MO. For Pending to be Yes, Good must also be Yes, and Scrap must be No. Since you took the items being returned directly out of inventory and did not use them, they should still be good and are returned to a site and location for good stock.

Call Activity Recording uses the pending status to mark items on an MO as returned. During a pending return, the system registers the return against the call and clears allocations for the returned items. However, no inventory is transferred. Complete the return later with MO Direct/Pending Returns (11.11.8).