I’m trying to finish grabbing a show, but Sonarr says the final season is #3, while the rest of the internet (i.e. torrent sites) says that season is #5. It looks like the first 2 seasons were split up into 1/2 seasons when originally shown. So while Sonarr is looking for Season 3, it’s finding the first half of what it thinks is Season 2.
Mine does that for futurama, but I just manually import that as they release.