These are the reasons that the invoices will not match and complete automatically.
There is no particular order to check as such, but all would cause an invoice to remain Outstanding.
* No purchase order in the system
* Product code does not match
* Codes on the invoice not present on the order
* Quantities/Pack size don’t match
* Price is outside of the tolerance
* Invoice line already matched to another PO
* EDI Invoice will only match to an EDI PO – Check EDI status Unavailable
* Supplier Reference does not match
* Purchase Order stuck at Status Awaiting Acknowledgement need to click Progress to Receipt in PO