I noticed that I can't active the new users. When I active them, they inactive themselves spontaneously.
Sounds like you've CBSubs set to require a subscription (no free registrations) within CBSubs > Settings > Global. This results in users trying to login without a subscription being auto blocked.
I disable all the CB plug-ins and templates. It doesn't work.
Repeat for 3rd party Joomla User and System plugins.