Use a recovery code

One of the ten codes from when you signed up. Each works once, and it will sign you in so you can add a new passkey.

Recovery code Hyphens do not matter, and the letters O, I and L are not used — if you see one, it is a zero or a one. Sign in with this code

Still have a device with your passkey? Sign in instead.
If the codes are gone too, the account cannot be recovered — not by us either. That is deliberate: anybody who could let you back in could let somebody else in.