In order to save your progress, don't forget to link your profile in the game to Google Play Games profile or Game Center and/or Apple ID profile, depending on your platform. Open 'Settings’, then tap the 'Link' button.
Linking a profile guarantees the safety of your game progress in case you decide to change your device in the future. If you need help with linking or restoring the game progress, message us at help@playquantum.com