Causing major headaches for people!
Changed mine and although I have managed to "reclaim" my server, my Lifetime Plex Pass is not fully working and I keep getting messages about the "Server is not available" or "Server does not exist" then it logs in.
The Plex Community Forums are a funny place at the moment if you like reading the "Salt Post's".
First issue I have had with Plex but honestly it's not looking good that so many issues can come around from what is labelled as a "Simple Password Change".