Security Key with PIN?

Two Factor Authentication
1

Hello,

I recorded my OnlyKey on Microsoft site, and now I have a PIN code associated to my key (different from PIN to unlock Key ) … I don’t find this feature in the doc.
Some site with MFA request this PIN. What is this functionnality ? How to manage it ?

Thank you

2

My bad … found on “Security Key Advanced” chapter …

3

Yes, this is the FIDO2 PIN. It requires a PIN for passwordless authentication.