What do you mean, "three factor"? The factors are something you have (telephone), something you know (secret or password), and something you are (biometric). Go

What do you mean, "three factor"? The factors are something you have (telephone), something you know (secret or password), and something you are (biometric). Google isn't allowing you to use biometrics like your fingerprint to log into your account; thus, you aren't using three-factor authentication.