If you're having issues with connecting to Facebook to save your progress, please, try these steps:
1. Make sure your internet connection is stable.
2. Make sure your username and password are correct.
3. Log out from the Facebook app if you have one (or delete and reinstall it).
4. Make sure you are logged out of your Facebook account in any browsers you are using on your device
5. Restart your device and try to connect the game to Facebook again.

Also
1. Go to Settings -> Accounts.
2. Tap Facebook -> Remove.
3. Restart your device and try to connect the game to Facebook again.

If these steps do not fix the issue:

1. Remove the game from the list of applications on Facebook. Facebook Help (https://www.facebook.com/help/204306713029340)
2. Restart your device, enter the game, and try to reconnect it to Facebook.