Your Facebook account maybe linked with his Microsoft account or Xbox account. First unlink your Facebook account, reinstall Facebook app (if you have since it integrates with your phone), restart the phone and play the games.
Unlinking your Facebook from Microsoft account
- Login your account at https://profile.live.com
- Click Manage
- Locate your Facebook account
- Click Edit
- Click Remove this connection completely
- Click Remove
Unlinking your Facebook account from Xbox
- Open your Facebook on a computer
- Go to settings page and navigate to apps
- Locate Xbox live and remove the app
Here are some reference links, if you want more information