Supplier Refund booking in PeopleSoft Payables

Could you please share how organizations typically handle supplier refunds in PeopleSoft Accounts Payable?

In our case, a PO invoice was created for $1,000, but only a partial quantity was received. The supplier subsequently issued a refund of $500, either via check or ACH. This supplier payment was recorded in Accounts Receivable; however, we are unclear on how to appropriately apply the $500 credit in Accounts Payable.

Creating an additional voucher (reversal or adjustment) results in a credit memo, even though the refund has already been received. We are seeking guidance on the correct AP treatment in this scenario. Thank you.

Thank you!