Buffer's 2 step login
Your account’s security is of the utmost importance to us, and we’ve added a two-step verification option for users. Whenever you log in to your account, after entering your username and password, you will be asked for a second authentication code that was sent to your mobile phone via text or free mobile app.
You can activate this feature by heading over to the My Account link at the top right of your Buffer dashboard and selecting Access & Password from the dropdown menu. From there, find the 2-Step Login section and click Enable. Enter your mobile number, complete the confirmation process, and you should be good to go!