iOS sync "forbidden"

Hey all,
I can’t seem to figure out what’s wrong with my iOS sync for obsidian between my iPhone and MacBook Air.
Basically, whenever I login or force reload I get a small popup in the top right that just says “forbidden”. I’ve tried clicking on the pop up, hovering my cursor over it and it doesn’t seem like I can do anything with it.

I’ve googled and searched the forums and can’t find anything about this error message. So, any help would be greatly appreciated. Thanks!

What I’m trying to do