A problem has been fixed when the maximum number of login attempts is exceeded.
A security question should have appeared (answer: air), but it was still asking for a confirmation code to a non-existent graphic.
This has now been sorted out and the security question is shown correctly.
If anyone has had this problem, you should try logging in again, but you will have to enter your Username, Password and the security question (air), before being logged in.
Don't forget to select "Log me in automatically..." before completing the login.