Drive locked by BitLocker - recovery key not found in Microsoft account.

My partner's laptop is locked by the Bitlocker recovery blue screen. This screen tells us the recovery key id to identify the recovery key. However, when she logs in to her microsoft account, there is no Recovery Key there.

How is this possible ? And how to find this key without loosing access to the content of the drive ? there are some very important documents for us there.

Best regards,