2. Force stop the apps which are running in the background by going to Settings > Apps, swiping right to the Running tab, tapping the app, then tapping "Force Stop."
3. Make sure you have enough free space, and all unnecessary apps are deleted, by looking in Settings > Apps.
If it was not helpful, try and reinstall the game.
Do not be afraid; you will not lose your progress if you follow these steps:
1. Write down your player ID (i.e. John#1a3b5) somewhere so our support team can restore account manually if something goes wrong.
2. Make sure you are logged into your Google account, and the cloud synchronisation is turned on in the Options.
3. Delete and reinstall the game from Google Play Store.
4. Launch it and complete the tutorial.
5. Navigate to Options and turn on Cloud synchronisation.
6. You will see a pop-up asking whether you want to restore your progress. Tap "Yes".
If nothing helps, please contact us and provide the detailed info about your device and OS version. We will do our best to help.