I had that problem earlier when subbing to a few communities. I solved it by tapping the “pending” which un-subbed, then subbing again and it worked. I chalk it up to performance issues. Growing pains.

That’s a common glitch on Lemmy right now. Subscribing to communities oftentimes gives you that message, but as far as I’m aware they’ll still show up in your feed like normal. I’ve heard if you click subscribe and then let it sit for a while it can resolve itself to show you as fully subscribed, but I haven’t had much luck with that.