Movie title uses filename even after movie is matched

The title of this posts says it all.

I have some movies (not very often but let’s say one every 15) whose title is the media filename e.g.

My.wonderful.movie.1080p.h264.mkv

I don’t have any problem with this but I would have expected Plex to correct the media name especially since this has been successfully matched.

Is this a wanted behaviour or perhaps something wrong with my settings?

Thanks

Reason: nonsensical Embedded metadata.

Go to Settings - Server - Agents - Shows - TheTVDB
In there, grab the line ‘Local Media Assets’ with your mouse and drag it downwards, so it ends up being at the bottom of the stack of active agents.
Repeat the same under
Settings - Server - Agents - Shows - TheMovieDatabase
+
Settings - Server - Agents - Movies - Plex Movie
+
Settings - Server - Agents - Movies - TheMovieDatabase

After doing this, Refresh Metadata on the affected items.