This is almost always due to naming or you file structure
https://support.plex.tv/articles/naming-and-organizing-your-tv-show-files/
L.A. Law (1986) <-Show folder
Season 01
Sometimes after you rename something you have to Plex dance it <-Click
If you’re still having a problem you can show us exactly how things are named and the file path
You might want to look into a renaming program
