For some reason have issue with sessions. So when i'm away for 5 minutes or trying to translate site, system tells "Session expired" and page categories stop work correctly. When triyng to refresh page, system redirects me to login page. That's very annoying when translating. Trying to reinstall all files and database but no effect. In authentication set 120 mins in Session Lifetime.
Please create a ticket with this issue. We need to have more details like your Installation URL, product detail etc.