Have you received a document from an administration that was not written in German?
Is the information not available in German? Are you unable to present your issue in German?
The legal requirements of language usage are very extensive. The Ombudswoman can inform you about your rights to receive a document in German language.
The permanent Languages Control Commission monitors compliance with the legislation on language usage in administrative matters. The Ombudswoman will help you to submit your complaint to this authority and monitor its development.
You can find the website here: http://www.vct-cpcl.be/de