Two-Factor authentication allows you to have an additional layer of security to your account.
You have to have your phone number verified in order to use SMS 2FA. Please tap here to see how to verify your phone number.
You will need to tap the box near "Enable 2FA via SMS", then you will be asked to enter the "6-digit" code that was sent to your phone.
Enter the code and tap submit.
If you didn't receive the code on your mobile phone, please tap "I didn't receive the code".
Each time you log in to your account, you will be required to enter a one-time passcode that will be sent to your phone.