Problem with language settings :: de_DE


we use a Raspberry installation AND FreePBX 2.11

The installation was uncomplicated. To understand the system it make sence to chance the languge at the admin panel :wink:

But this is not so easy ;-(

We recocnised the button in the right corner (language) - to select german etc…
But if we change this nothing happends. After reload everything is in english.
We have install some languages like de_DE-Utf8 and others ans selected de_DE-Uft8 as normal lang.

So what is the problem? THX for help.