Red “banner” with a 1 appears on wp-login.php

hi, this odd error type red banner is appearing on the login page. We can’t work out why. We moved domain and have noticed it since, maybe it is related or coincidence. Advice on what might cause it is really welcome! Thanks.

Edit: It seems to have stopped being an issue on Chrome but still is one on safari and firefox.

• This topic was modified 11 months, 2 weeks ago by ablak1. Reason: clarity

The page I need help with: [log in to see the link]