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
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This opens the draft credit request, allowing you to make any changes before selecting Order to complete creating the credit request.