That means someone is currently on that account. If you haven't shared your account with anyone, you can reset your password by going to http://playnewz.com/forgot_pw.php and entering the email currently registered on your account.

If you were just logged into the account before that, just wait a few minutes for the server to resync with your account and you will be able to join the account. 

Do not spam "LOGIN" and just have a little bit of patience. 

If the issue persists, please open a new ticket.