@jikodesu Thanks.
What confused me was I had followed a # link from another users profile on a different instance. Which seems to break it. Because looking directly at another user's profile technically puts me on another instance im not signed into.... if that makes sense.

Its the same thing for following people directly. If I click a link to their profile and its on another instance, it wont let me follow them.

@kes3d @jikodesu you should be able to, if both your instances are the same build of the mastodon protocol. If you can't, that's usually a sign you're both in the Fediverse but not on the same protocols (this includes forks of the same protocol). For instance I can't follow directly anyone on original mastodon builds (I'll do it on client or via the search function) because my instance is on a fork. Hope that helps!
@cendawanita @jikodesu Cheers for the info. It is just a bit confusing because its all presented through the website and so all looks like it should work coherently.