Different associated companies $ / $ (account $)

What causes this issue?

The number of the associated company must be unique for all document
items. In this case, there are at least two different companies or a
company in connection with a business partner that does not belong to
any company. There is an incompatibility due to the fact that the
company from the supplier master record is &V1&, whereas the one from
the G/L master record is &V2&.

System Response

Such a combination is not accepted.

How to fix this error?

If you entered account no. &V3& manually, correct the number. Otherwise,
please contact your system administrator.

Error message extract from SAP system. Copyright SAP SE.