@DaultRadio @jentaub

If you enter the full account address in the form "@ user @ server" without the spaces, as copied directly from their profile pages, it should work.

If you only enter part of it, it may not work because your server won't know which server to check.

If it's not working for you right now, it sounds like your server has a bug or a delay on it, possibly caused by the huge number of signups in past few days.