Are you able to elaborate on that? What is the session problem that you're having? I was able to login to your community without issues. If you have visited on the browser before, I would recommend clearing cookies/cache just to start fresh to ensure nothing was corrupted.
Do you allow members to delete their own content? If so, users would have the ability to delete their own topics. That is completely normal and what you have instructed the software to allow. If you can provide a topic URL and member name/id, we can certainly verify that.