I had a similar situation when I installed google authenticator key for additional protection of akks. The thing was that I lost my old phone and I had to find out how to protect yourself in case the iPhone crashes. In fact, Transfer Google Authenticator to New iPhone is not so easy if you are not prepared in advance, and this is exactly what happened to me, because I did not make any backups. Now I’m trying to use the built-in exchange function for authentication more often, so that there are no problems with google authenticator new phone. So often make backups of important information and store it more securely, do not make the same mistakes, because there is a risk of losing important information, as it was with me.