Did you change your password on the forum, here by clicking profile settings.
Or did you actually try to change the game password by using the yellow box next to the banner on the home page, clicking "user details"? Changing the forum password will not affect your game password.
If you have another account, I'd try to play the game with that to ensure that it's actually the account you speak of that is being the problem and not your actual connection to the game.