The code "Error 10" is related to issues with Google Cloud save. Before you start, make sure you have Google Play Games installed and updated.
Here's a workaround for you to try:
- Make sure the game is closed
- Clear Google Play Games cache and data
- Open your Settings app .
- Tap Apps & notifications See all apps.
- Scroll down and tap Google Play Games.
- Tap Storage Clear storage.
- Re-open the Play Games app.
- You can also re-try these steps for Google Play services and Kingdom Rush
- Open the Google Play Games app and let it refresh
- Find the Google Play Games library and launch the game from there