make domain users member off local users trough gpo

hello,

I have a problem, most of the users are local admin. I dont want this because they are installing junk.
I have have made the following gpo, in restricted groups I’ve created a new group called users with members domain users and member of users. Now the user gets deleted (no user at all) but still remains local admin??? is there something I doing wrong or is there maybe a regfix or something like that.

regards sebas