Don’t seem to be able to change mine.  It’s weird.  I delete the current one, upload a new one, at it’s still the old avatar that appears.  Don’t know if anyone else has that same issue though.

It works fine when I change mine. Forgive me, but I assume you tried refreshing? What happens if you try to use an avatar from the default set?

I did try refreshing.  It works now though.  Weird.  I logged back in and my old avatar was still there, but I saw your post commenting on it so I refreshed again and there it was.  Hmm. 
Thanks DH.