Received ISO country code for language is invalid

What causes this issue?

SAP does not recognize the node-set 2 figure ISO country code &V1& for
the basic document language or appendix language.

System Response

The language is ignored. The logon language is set instead.

How to fix this error?

Inform the node manufacturer that the ISO country code is invalid.

Error message extract from SAP system. Copyright SAP SE.