Unfortunately, I haven't. It looks like I have lost access to that vault. Fortunately it was my daughters vault and she had not populated it all that much. If it was my vault it would have been a disaster.
It looks like you need a back door if you are using the Lastpass Authenticator because in order to restore the authenticator from backup you need to be able to login to Lastpass. And as you know to login to Lastpass you need the Authenticator.
The backdoor available is SMS or a Text Message. I haven't looked at this option but I'm not to crazy about that. And yes, this must be setup before you are locked out so unless you have it setup you out of luck.
I'm going to see if using other Authenticator like apps is a better solution. I liked the feature that the Authenticator backs up all the codes in the Lastpass vault but it's not exactly ideal in our situation.
You should be able to find on the Lastpass support page a link to be able to report this specific case. The techs will ask you to provide them with five websites that you remember being in your vault. If you are able to answer their question they will open the vault for you or something. Not sure. My daughter was not able to answer all of the questions so she is out of luck.
I had a hard time finding that link and I didn't take notes so I can't help you with that.
I hope this helps.
