I've lost my Multifactor Authentication, how do I disable it?
Whenever you login with Multifactor Authentication enabled, you are prompted to use your authentication code to login. Underneath the entry field for your code , there is a link entitled:
"If you lost your device, click here to disable authentication."
"I've lost my device."
Clicking this link will send an e-mail to your LastPass account e-mail address (or security e-mail address if you have set one), that will contain a link that will temporarily disable your Authenticator. If you do not receive an email, please see https://lastpass.com/support.php?cmd=showfaq&id=6386.