Automatic Clearing F.13

Hi,

It was noted that my configuration field (in OB74) for automatic clearing, F.13 is differ than the field seen in F.13.

In OB74, the selected fields are ZUONR(Assignment), GSBER (Business Area) & VBUND(Trading partner).

But in F.13, the matching fields are Ref Key3, Purchasing Doc and Item.

Please advise why there is a difference & where else the configuration can be done.

Thank you.