Same here since Feb 19.
Good news : it's working today Mar 13.
I had been getting this same error msg since February 19, 2017 and had re-tried many times to see if it was ever corrected. I had also tried 3 different browsers and both PC and smartphone to ensure that it was not just a compatibility issue with a particular browser.
So today March 13th upon trying, it actually worked !!!
It told me that registration was completed and that I'll be receiving a confirmation email shortly. So apparently whatever bug they had introduced prior to Feb 2 (the oldest date I saw on-line that people have complained about) has finally been corrected.
So if you haven't tried again recently, give it a try now.