Why are all my events and challenges gone? Also my daily spin.

Hi and welcome to the King community.

Please do the standard trouble shooting by log out, update your game application, restart your device and login, if playing through browser please clear cache/ history. And login again.

After login again whatever bonus feature you will get that is currently available in your game. Other than that, features might be temporarily unavailable as features come and go. They are not the permanent part of the game and can be replaced or unavailable at any time. Always keep your game up to date and hopefully it might return to you.