You need to keep reloading the page - CtrlF5. I've had a similar though less serious issue this morning (just now). I think there is something in the thesis proposed by one of the other Superusers that the system is incapable of coping with large numbers of log-ins at busy times when people are going on to check their e-mail.
Superuser 2017/18 Use Kudos to say thanks Mark answer as "helpful" only when the problem is solved Please don't send me private messages unless I ask you to. I do not work for VM. The advice I give is based on my best understanding of VM policy and practice. You rely on it at your own risk.