I have only one Plex server running. If I search for an actor, results will be displayed on two systems (please see picture). I can check one source and there is one set of movies, all of them play fine. If I do the same search and select the other source, there is a separate list of movies all of which play fine. It seems Plex thinks I have two servers. I did migrate this server from one machine to another.
I figured out a solution in the event anyone else here shoddy ever face the same issue. I found that if I dragged one of the movies out of the physical folder it resides in, it would then be removed from the second Plex server with the same name. I then copied it back and it would then jump to the proper server when viewed in Plex.
After this showed to be promising, I removed my library mappings in the Plex server to the folders contains my physical movies files. It took a while as the scan completed and as expected no movies were found. I then added back my library mappings, all the media was scanned, and now only one server is showing with all the movies. Go figure.
