You can set up SMS authentication as MFA (Multi Factor Authentication) with the following steps.

  1. Click “Setup” of SMS.
    image tooltip here

  2. Enter your phone number including country code.
    image tooltip here

  3. You will receive a verification code. 
    123456 is your code - Listman

  4. Enter the verificatoin code to the form and click “Verify code” button.
    image tooltip here

  5. A check mark will be shown which indicates SMS authentication is enabled.
    image tooltip here

  6. A verification code will be sent to your phone number when you login next time.
    image tooltip here

  7. SMS authentication can be disabled by clicking “Disable”.