Your database is corrupt.
From Plex Media Server.log:
Apr 02, 2021 22:47:33.455 [0x14b6dd5ea700] ERROR - SQLITE3:(nil), 11, database corruption at line 79051 of [bf8c1b2b7a]
Apr 02, 2021 22:47:33.455 [0x14b6dd5ea700] ERROR - SQLITE3:(nil), 11, statement aborts at 26: [select tags.id as 'tags_id', tags.parent_id as 'tags_parent_id', tags.metadata_item_id as 'tags_metadata_item_id', tags.tag as 'tags_tag', tags.tag_type as 'tags_tag_type', tags.tag_va
Apr 02, 2021 22:47:33.455 [0x14b6dd5ea700] ERROR - Soci Exception handled: sqlite3_statement_backend::loadRS: database disk image is malformed
You have three choices: repair, restore from backup, or delete & start over. If you choose the latter you will have to re-create your libraries, shares with users, etc. Your movies/tv shows/etc are not affected.
Here’s some relevant support articles:
Repair a Corrupt Database
Restore a Database Backed Up via ‘Scheduled Tasks’
Here’s a thread from the server-docker section regarding fixing database corruption:
Problem With Corrupt databases
