What file type are your movies? If they are .mp4 or .m4v
Is ‘Local Media Assets’ on the top of the list under
Settings - Server - Agents - Movies - Plex Movies
+
Settings - Server - Agents - Movies - TheMovieDatabase
?
If so, grab the line ‘Local Media Assets’ with your mouse and drag it downwards, so it ends up below the lines ‘Plex Movie’ and ‘TheMovieDatabase’.
Then Refresh the movie and wait ~ 3minutes.