Cannot determine language for country &1

What causes this issue?

In accordance with your settings in the IMG activity
<DS:SIMG.GGA_400_120>Specify Languages</>, you want to output dangerous
goods data on the delivery note in the language of the forwarding
country.
The system could not determine the language of the forwarding country
using the country key.

System Response

No dangerous goods data is output in the language of the forwarding
country. Processing is continued.

How to fix this error?

In the IMG activity <DS:SIMG.SIMG_CFMENUSAPCOY01>Define Countries</>,
enter a language key for the country &V1&.

Error message extract from SAP system. Copyright SAP SE.