My experience is that they are VERY understanding about situations like this. Last month, they were down, off and on, for over two days. I, too, was trying to get reports submitted.
After they came back to work on Monday, I got a very nice e-mail apologizing and admitting that yes, they had website problems. They extended the report time so my reports were accepted.
OTOH, when I was kicked off using Firefox, I then tried Chrome. You might try a different browser before giving up. And you just might try again later, and again tomorrow. I believe they can see that you have logged in and attempted to complete the reports.
Good luck, and let us know what happens.