There are a couple of things you can do to reduce the chances of your account being permanently lost.
First, if you are over the age of digital consent in your country – the age varies between countries, but in most places it is between 13 and 18 years old – you should link your game to a Google Play Games or Game Center account from the Accounts tab in the settings menu. Linking your account in this way means that you’ll be able to restore your progress on any device, just by logging into the appropriate Game Center or Google Play Games account.
As well as linking your account, we also recommend that everyone makes a note of their account ID. This ID represents your account, and keeping a note of it means that, even if you have trouble restoring your account using your Game Center or Google Play Games account, the support team will be able to locate and recover your missing profile from the game's servers. You can find your account ID at the bottom of the Support tab in the settings menu.
Note: your Account ID is sensitive information and should never be shared with anyone other than SEGA staff. Be careful not to show your Account ID when sharing screenshots, and never share it with other players for any reason.