Hi Maria,
There is difference in calculating debit and credit amount for purchase returns and this is standard system behavior.
Case 1:
If your purchase return based on Good receipt PO, there is no difference in amount, similar to GRPO.
For example, GRPO price 100, same 100 will be copied in return entries.
Case 2:
If your purchase return not based on GRPO, then system will consider item cost, not price in the purchase return document. There is no separate posting for variance amount.
For example, item cost 75, same 75 will be debited and credited.
Thanks & Regards,
Nagarajan