What happens when I activate 2FA? July 07, 2022 08:00 Updated The One Time Passcode (OTP 6-digit number) will be sent to the email address you used to register for the McDonald's App. Related articles I did not receive the two-factor authentication (2FA) email. What should I do? What happens if I do not authenticate myself with 2FA? How can I authenticate my app with 2FA if I happen to forget my email/password?