Lost your phone? Enter one of your recovery codes instead.
Every sign-in now needs a code from an authenticator app. Scan this with the app on your phone, or type the setup key into it. Do not photograph or share it: it is the second key to this account.
Two-factor sign-in is on. These recovery codes each get you in once if your phone is lost. They are shown only now: print them or write them down, and keep them with your important papers.