If this issue persists on an iOS device (iPhone or iPad) after an update, please follow these steps:
  • Open your device Settings and scroll to "Empire" at the bottom. Then Toggle Setting "Reset account" to on:

  • Start Empire: Four Kingdoms. In the "Reset account data" dialog select the green button. When you see the "Please restart the app" dialog, close Empire: Four Kingdoms app completely by swiping up in the currently running apps:

Running Empire: Four Kingdoms again should now start a new game, and you can login to your account using the "Login" buttons.