Two problems: (a) database corruption and (b) naming & organization.
Database Corruption
From Plex Media Server.log: Sep 05, 2024 08:57:45.151 [190901533888] ERROR - [DatabaseFixups] SQLITE3:0x1, 11, database corruption at line 72267 of [a29f994989]
You’ve three options: repair, restore from backup, delete and start over.
I’m not sure repairing is an option on the Shield, as the normal methods require access to the operating systems. You could install Plex Media Server on a Windows/Mac/Linux box and try to repair them there, then move the files back to the Shield.
You can use the Plex DB Repair Utility or issue the commands from the OS command line:
You can try restoring from backup files. There is no guarantee that the backup files are not corrupt themselves. You will have to check Plex Media Server.log after restoring a backup.
See Restore a Database Backed Up via ‘Scheduled Tasks’.
If unable to repair or restore, then you’ll have to delete the database files and start over. You’ll have to re-create the libraries and re-share them with any people with whom you share libraries. Stop Plex Media Server, delete the database files, then restart Plex Media Server. A complete uninstall is not necessary.
Naming & Organization
Plex Documentation → Your Media → Naming & Organizing Your TV Show Files
While the database corruption is the main cause of your problems, you do need to straighten up file naming and organization.
Example: Multiple TV series are named in this manner
/storage/QNAPNAS/Plex Data/TV Series
../1971 The Year
..../1971.The.Year.That.Music.Changed.Everything.S01E01.1080p.HEVC.x265-MeGusta
....../1971.The.Year.That.Music.Changed.Everything.S01E01.1080p.HEVC.x265-MeGusta.mkv
Correct: Use a season folder
/storage/QNAPNAS/Plex Data/TV Series/
.. /1971 The Year That Music Changed Everything (2021)
..../Season 01
....../1971 The Year That Music Changed Everything (2021) s01e01.mkv