Country key & is not defined

What causes this issue?

The country key &V1& is not in the country table.

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 the input. Check the country key for the country in question in
the implementation guide, if necessary (<LS>General settings</> ->
<LS>Set countries </> -> <LS>Define countries</>).

Error message extract from SAP system. Copyright SAP SE.