The problem was that it was forgotten to add the domain admin group to the right mediawiki place or group. Very thanks an Robert Vogel from bluespice on SourceForge that help me to find out the problem. So everything should only edit in the webinterface. With a command to add your user to the right admingroup, this is working fine.
docker exec -it hungry_haibt bash
cd /var/www/bluespice/
php maintenance/createAndPromote.php --custom-groups "Domain Admins" --force youusername