I upgraded my Mac mini (2018) to the newest Plex Media Server several weeks ago. Since that time it dropped several seasons of TV shows and would not add new shows or episodes since that time. I removed the TV library and had it rebuilt and it only picked up portions of a season and didn’t pick up several shows at all. I have since added new episodes and shows and Plex will not pick them up. Please do not insult my intelligence by telling to select “Update Libraries”. The last time this happened I had to remove the whole program and start fresh. If that is the case I remove the whole program, cancel my subscription and never use Plex again!
Please verify the Plex Media Server version. 4.69.1 is the version of Plex Web. Settings → Server_Name → General or Settings → Authorized Devices
Are your media files stored locally, on an external drive, on a network drive, etc? Might it be a permissions problem where Plex cannot see the files?
For one of the troublesome TV shows, please show how you have your media named and organized - directory listing, screenshot, etc. Include the full path to the files, and which folder has been added to the library.