DeletedUser370
At this point I'm wondering if you have double-checked that the key is actually registered to your account. Are you able to sign in to Bitwarden from other devices (if you have another device available)?
Yup, I signed out of Bitwarden on my Ubuntu laptop, signed back in and was prompted for the YubiKey, inserted it and logged in no problem.
Can confirm that if I go into the WebVault I see the YubiKey registered under "Passkey: Use your device's biometrics or a FIDO2 compatible security key."
Drilling down into that menu I see my key listed under "Turned on, This two-step login provider is active on your account." WebAuthn "YubiKey (Migrated from FIDO)"