For Procure Wizard to map a EDI credit note back to a purchase order number on the system, there is two essential parameters that are needed within the EDI credit file sent in from the supplier.
Parent invoice number - this must be the invoice the credit has been raised against (this invoice must also be uploaded into Procure Wizard).
ShipToCode/PurchaserUnitID: Where a valid parent invoice number has been found against a Purchase Order number. A secondary check is performed to validate that the Purchase Order number found is for the correct purchaser site/customer. importedCreditNote.ShipToCode == suborder.purchaserunitID
Account Code: Where the unit/site ID is missing we will attempt to match the credit via the account code provided.
It's important to note that if a credit lands in Orphans that when the error is corrected the system does not redo the above checks automatically to sync the credit back to the parent order/credit.