Plex Not Detecting New Files

Server Version#: 1.15.4.993
Player Version#: 3.95.2
Plex has been detecting my files correctly for years on my Synology NAS. My TV episodes are downloaded automatically and renamed automatically by Sonarr which is in a Docker container on my Synology NAS.

I am completely unsure what has changed that has stopped Plex identifying correctly named TV episodes placed into the correct folder locations.

Seeking advice on how to identify the issue and get this operational.

Thanks in advance.