Two-Factor Authentication (2FA) lets you secure your account so that you login with both your password and an additional secret number that changes every 30 seconds on your phone or in another TOTP authenticator app.
Some of the most popular 2FA apps are Authy, Google Authenticator, and Microsoft Authenticator.
To turn this feature on, go to ☰ → Account and when you scroll down in the Account tab you will find the "Enable 2FA" button.
After you click on the "Get Started" button you will need to open the authenticator app on your phone and scan the QR code or manually enter the text code. After you add Marvin to your authenticator app, enter the 6-digit code into Marvin.
IMPORTANT: Make sure to store the recovery codes in a safe place in case you lose access to your Authenticator. Without access to the authenticator app and your recovery codes, you won't be able to log into your Marvin account.
You can always disable 2FA, as long as you know your password and have the current 2FA or recovery code.