Ranger usersync is not actual

Hello,

we have a HDP 2.2 cluster and would like to use Ranger for authorization. Ranger properly imported many user with their correct affiliations to UNIX groups, but it failed for three users. If I do
id usera

I get
uid=20105(usera) gid=10217(groupa) groups=10217(groupa)

But in the web interface of Ranger I see that the usera belongs to groupx. I have tried to recreate the user but it did not help. Ranger ‘thinks’ that the usera belongs to groupx, and I could not find a way to change it. I do not see any error messages in ranger/usersync apart from SSL handshake due to Ambari Metrics. The sync messages look good:

19 Aug 2015 15:47:37 INFO UserGroupSync [UnixUserSyncThread] – Begin: update user/group from source==>sink
19 Aug 2015 15:47:37 INFO UserGroupSync [UnixUserSyncThread] – End: update user/group from source==>sink

Any ideas?