I just found that I'm getting the infinite spinning issue when commenting on a post in !enshittification@lemmy.world and not sure what the issue is as it is the same on two different computers.
I'm not banned from that community and there is nothing listed in the modlog of that community either as I just checked this, and I do select a language before trying to post.
Ok, then please check your Developer Console ( on desktop press F12 ) and check then "Networks" Tab, and check for errors ( red ) click on it and in there, you should see a "Response" tab and check what it is happening.