Metadata not refreshing automatically

I’ve been using Plex server on my PC for many years without issues. Recently I purchased a Synology NAS and installed Plex on it. Everything works fine except subtitles. Even after setting everything up as before, shows that I download never get subtitles added.

After searching online, I found that if I clicked on ‘Refresh Metadata’, it will download the subtitles I need. However, this is a manual process for most of the time. If I’m lucky it will download for some shows. I’m not sure what else I can do as I can’t refresh this from my mobile app or Android TV app. I always have to log into Plex from my browser to do it.