You hope that you have printed backup codes for whichever services provide it, or alternative auth, or you go through ID verification to regain access. Not muc

You hope that you have printed backup codes for whichever services provide it, or alternative auth, or you go through ID verification to regain access. Not much else you can do, the point of 2FA is that you can't get in without it. Some services let you store multiple keys. So you can own a separate yubikey that you keep in a trusted place eg deposit box.