Harmont docs
APIErrors

passkey_unknown_credential

The passkey you presented is not registered on this account.

HTTP status400
typeinvalid_request
codepasskey_unknown_credential
Default messageThis passkey is not registered.

When this happens

The credential your authenticator offered is not on file. This usually means the passkey was created for a different account, was removed from your account, or you are signing in to the wrong environment.

How to fix it

Try a different passkey, or use account recovery to register a new one. If you still have access through Google or GitHub, sign in that way and add a fresh passkey from settings.

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