Google Authenticator is a free mobile app available for Android, iPhone, iPad and blackberry, which is used to generate temporary login codes valid for 30 seconds. These codes can be used as a secure form of two factor verification providing an extra layer of security for your account. If you have a supported mobile device it is highly recommended you enable Google Authenticator on your My Wallet account.
Simply the app will give you a code which you must provide before you can login.
Google Authenticator is a mobile application that allows you to generate 2-step verification codes on your smartphone without a network connection. We recommend users with smartphones to use Google Authenticator to generate verification codes instantly to sign in to their Google Apps accounts. google.com
Open the App store or Android market and search for "Google Authenticator". Download and install the app as you would normally. For more information please see google support
When you next login you will see an extra text field
Simply open the google Authenticator app and type the numerical code into the text box. Each code is only valid for 30 seconds, so be quick!
No problem, simply complete a two factor authentication reset request.