I personally have zero issues, been using it for a while now, both movies and TV shows and even music.
Have you tried to manually identify the show, to verify that you are indeed able to connect to it?
Otherwise, no sure if you have found it already, but there are some instructions on how to structure your directory to make it easier for jellyfin to identify your shows and download the related metadata, just sharing for other people who might be interested too: jellyfin.org/docs/general/server/media/shows/