This usually happen if you have attempted to access cpanel, webmail or any other service in the server, many times, with the wrong user/password combination. Our security system detect these failures and block your IP.
Simply accessing your Client Area our system will detect your IP, check if is blocked in the server and will unblock it. You can also use the Unblock IP option in your Client Area panel tu unblock other IP different than the current one in your connection.