Cannot set the language environment for language &

What causes this issue?

You attempted to switch to a language environment for the language
specified in the error message. This language is either invalid or not
configured in your system.

System Response

An error message is displayed.

How to fix this error?

Check whether the application really does require the specified
language. If not, there is an error here.

Procedure for System Administrators

During the processing of a SAPscript document, the language environment
had to be changed because of the language requested. Permitted
languages are usually set with the profile parameter
'zcsa/installed_languages'. The required language was not contained.

Error message extract from SAP system. Copyright SAP SE.