If you ever manually change a title inside Plex you have to lock the field so it doesn’t change when you refresh the metadata
You really should never have to do that unless the show itself can’t be matched. If the show matches the show titles should too unless it’s a brand new show that doesn’t have a title yet.
Every title inside your file system needs the “s01e01” format for TV shows
The Mandalorian (2019)/Season 01/The Mandalorian - S01E01 - Chapter-One - The Mandalorian (how it should be on your file system)
I’m not sure where Plex is getting “The.Mandalorian.2019.1080p.BlueRay…x264.mp4” but a title like that shouldn’t exist in or around a TV show folder or you will have problems
If you changed the name on your file system and a rescan/refresh metadata isn’t working you might have to plex dance the show
