In vendor master, you've defined another "invoicing party" as partner rather than vendor itself.
In app "Manage purchase order", you create a purchase order. You find the "invoicing party" is still the vendor but not the one assigned in vendor master.
- SAP S/4HANA Cloud All versions
Reproducing the Issue
- maintain invoicing party in vendor master->partner
- launch app "manage purchase orders"
- create a purchase order
- invoicing party is still the vendor name of the PO
"Manage purchase orders" app only suggests the supplier itself as invoicing party.
Check the "invoicing party" during PO creation, and you can consider to manual adjust it if necessary.
KBA , MM-FIO-PUR-PO , Fiori UI for Purchase Orders , Problem