("Failed to log in or register new account")
Same with one of my PD account (the other logs, no problem)
do you have 2fa enabled and are you entering the correct key?
are you sure you are entering the correct username and password? BOTH are case sensitive (remember the screen name and your username are not the same thing at JD)
Does your password have any weird (arabic, mandarin, that kind of thing) characters in it?
Are you sure you selected just-dice as the site before trying to log in (default site is PD)