To login properly using Words With Friends 2 App, please check these steps:
1. After you launch the app, there's an option to load your game using Facebook if you already linked the game to your Facebook account.
2. If you are not connected to Facebook, you can sign up for an account using the “Sign in with Email” button to enter the email address and password that you’ve used when you created your original account.
Note: Please make sure that you enter a correct email address to avoid creating a new account.