The Manage Account option is to allow the setting up of the Payments on the account which requires 2FA for Security. This option is limited to the tenant owner.

The User Menu is displayed by selecting the People icon on the Top Right of the Web Page.

Select Manage Account from the User menu

Selecting Manage Account will open a screen to show the following:- 

The user can now either scan or copy the codes for their authenticator app and enter the authentication codes and press "Test Codes" to verify the access is permitted.