If you would like to start from scratch, you'll need to create a new game account.
To do that:
- Uninstall Little Big Robots;
- Log in to Game Center with your AppleID and make sure that it doesn’t already store any Little Big Robots progress: Settings → Game Center → toggle on → continue with AppleID);
- Install Little Big Robots;
- Launch the game;
- In order not to lose access to your new game account, connect it to a new AppleID: In-game Settings Menu → Game Center ‘Connect’ button.
⚠ NOTE: Unfortunately, it’s not possible to start over using the same AppleID