Message SAP /ISDFPS/MM_CS043 - Sender of the assgd PReq is not op. in the cur. log. syst. in PO &1/&2

Diagnosis
Purchase order (PO) item &V1&/&V2& refers to a purchase requisition(PReq) in which the sender is not operational in the current logicalsystem.

System Response
The PO item cannot be created or changed in this system.

Procedure
If you want to process PO item &V1&/&V2& in this system, delete thereference to the cross-system PReq.