The language code used is invalid. It is an unknown code.
The language code indicates the language in which the data is offered. This must be an indication that is equal to the indications usable within the database.
Solution:
Check which languages are valid and change the language code in the import file with a code for an allowed language. You can check which languages are valid by selecting Language from the System management tab.
Additional data languages are possible, this is an additional service. You can contact EZ-base for this.