If you want to post a credit note, the following options are available:
On the tab, select the check box if you want to post the ledger transactions equal to the debit note ledger transactions except for the sign (minus (-) credit on the revenue account). If not, the debit note postings are mirrored (debited from the revenue account) when you post the credit note.
Select the if you want returned quantities to be updated to open order line quantities (back orders). If your customer does not want a new delivery of the returned items, do not select this option.