If the game is not loading due to the error message: "User opted out of platform" it means that your game is connected to Facebook, but you have disabled using the Facebook platform from 3rd parties.
In order to get back to the game, follow these steps:
- Open up Facebook website or mobile app and go to "Settings"
- Click "Apps and websites"
- On the "Apps, websites and games" section, click "Edit"
- Click "Enable Platform"
If you still get the error after these steps, please fully uninstall and reinstall the game (iOS) or use 'Clear Data' from the Application settings (Android).