OK, and do you know about the filter sidebar? It lets you turn filters on and off; see below, by clicking that gear menu toward the top right, you get a slide in menu, with available filters:
Let me know if choosing Class or Group from that sidebar fixes the issue for you.
If that’s the issue, you’re not the first to stumble on this problem. I think it’s a bona fide UX bug, in that it’s a bit too subtle.
Let me know – thanks!