Locked out of server and Plex reference article on how to get in didn't work (for me)

Plex Media Server NAS & Devices
2

See Synology FAQ 15: Claiming & Connecting to a troublesome Synology server.

If that does not work, please provide a set of server log files (FAQ 1).

  1. In Package Center, stop Plex Media Server.
  2. In File Station, go to /PlexMediaServer/AppData/Plex Media Server. Compress the Logs directory to Logs.zip.
  3. Upload the zip file to the thread (Drag it into the message window. It will insert at the cursor location).