Atakama does not rely on usernames, passwords, or account credentials to protect your data. Atakama instead relies on devices that you trust (your computer, your smartphone, your tablet, etc.) running Atakama's software.
If one of your devices were to break or become lost, you may not be able to access your protected files until a replacement for that device is brought online. Atakama cannot "reset your password" because Atakama has no concept of passwords.
Your spare keys are there to ensure you always have access to your Atakama-encrypted data. You can use your spare keys during the device replacement process to confirm that only you - and not an attacker - are performing the replacement using a new device that you trust.