When you switch agents like that back and forth it can cause damage and odd behavior in the way your library functions
I would update back to the new Plex scanner agent and rescan/refresh metadata
Any files that are still a problem you may have to Plex Dance ← Click
If you still notice problems with certain files first look at naming. With the new scanner this is most likely your problem but if something is still not matching put that file in a newly created library as a test to see if it works there
