FreeRadius Help

I have a freeradius server for authentication. I have Mikrotik setup as my NAS. Somehow my users that were connected yesterday, are getting messages they are already connected and cannot re-authenticate. They are not active in my Mikrotik. I issued the following: service freeradius start service freeradius stop Figured bouncing the service would take care of this, but it doesnt. Now not all users are affected, just some. I need an easy way to clear OLD sessions, setup as a cron job, or some manual way. Or a more permanent solution, its like users are being cached because I connected to the internet behind a NAS, powered off the computer and Mikrotik 2 days ago and it still shows me connected. You must be proficient in FreeRadius! When bidding, please tell me your experience using FreeRadius!