try {
  const { token } = await auth0.getAccessToken({ audience: 'https://api.example.com' });
} catch (error) {
  if (error instanceof MfaRequiredError) {

    // Get available authenticators
    const authenticators = await auth0.mfa.getAuthenticators({
      mfaToken: error.mfa_token
    });

    // Enrollment
    const enrollment = await auth0.mfa.enroll({
      mfaToken,
      authenticatorTypes: ["otp"]
    });

    // Initiate challenge
    const challenge = await auth0.mfa.challenge({
      mfaToken: error.mfa_token,
      challengeType: 'otp',
      authenticatorId: authenticators[0].id
    });

    // Verify code
    const tokens = await auth0.mfa.verify({
      mfaToken: error.mfa_token,
      otp: '123456'
    });
  }
}