The Plex Media Server was shut down by you or your OS:
Jun 06, 2019 04:49:32.490 [0x728ff450] DEBUG - Shutting down with signal 15 (Terminated)
Just restart PMS with sudo systemctl restart plexmediaserver.
If you did not kill PMS deliberately, please try to disable DLNA and the “Advertise as Player”. Both features have bugs right now.
https://support.plex.tv/articles/200350536-dlna/
