Are you connecting and claiming your server via an SSH Tunnel? Or are you attempting to claim the server via X2Go
You may have to double-back and attempt to claim it once more... I would advise the X2Go method (as linked above). You can additionally do this method to confirm that your Plex is active and that this is indeed a caching issue that will more than likely expire itself out on it's own.
If you like, you can PM me the details of your server/plx and I will login to see if this is just a localized issue, i.e; Just your browser caching old data. Numerous people have been through this with Plex and it's always caching issues.