Different order supplier & in PO &

What causes this issue?

You are entering a goods invoice and entered the allocation criterion
<LS>Selection supplier</> &V3&.
Purchase order &V2& was placed with supplier &V1&; this is why it is not
selected.
INCLUDE MM_IV_MELDUNGEN OBJECT DOKU ID TX

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Check your entries and make any necessary corrections.

Error message extract from SAP system. Copyright SAP SE.