TT online automatically disables 2FA (called "2-step" by TT/Intuit) after Authenticator is enabled; this is a coding error. Unfortunately, TT also has an infinite loop on "Continue" when trying to re-enable 2FA if the code is to be sent via voice phone call (as it should be since clear-text SMS has been deprecated for many years and is a serious security risk). However, the path to reset login security does NOT have this bug and, once 2FA is enabled again, then Authenticator works as expected, with Authenticator flagged as "primary".
BOTTOM LINE: TurboTax/Intuit requires both settings to be enabled.
