no this is not about bitlocker. ( i don't use bitlocker!)
this is a secure boot feature of windows 11 after swapping hardware or disabling it in the bios. you have to verify that you are you (when logged in with a microsoft account)
your login screen is locked and requires that you log in into your microsoft account again, then type in the key that you got per mail and after that you have to reset your PIN.
the problem is that you can not log in again without a internet connection.
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