You can request a credit on a purchase order from your supplier.
To request a credit for a purchase order, go to the Supplier module and open the Purchase Orders section.
Locate the purchase order you want to request a credit for, and click the Spill button at the end of the row.
Choose Request Credit.
This opens a window, allowing you to chose the Date of Pending Credit Request. Select Confirm to create the credit request
This opens the draft credit request, allowing you to make any changes before selecting Order to complete creating the credit request.