If you’ve deleted a Plex media server from your account, or rebuilt one with a different name, you may notice it is still showing up with a message stating: “We’re sorry, but we can’t reach this server.”
This is probably due to cached website information in your browser.
Try using another browser and login to the Plex.tv website. You’ll likely not see the deleted servers anymore. If so, then clearing the cache and web files on your other browser should fix the problem.