I had same error code until I read someone who was successful advising to open several pages and try simultaneously!. it worked!
I was able to register after spending all night till early morning at it!. But since then to log into my account has been really frustrating. most times when I try the system logs me out its a real punishment.
Try opening several pages at a time and keep trying, simultaneously though I use 4GLTE it should not be the reason, I think there are just too many of us at it. Good luck mate