If you don't you may lose what's not on backups. We just went over all this at https://www.cnet.com/forums/discussions/bitlocker-recovery-help/ which covers the key in question.
I have a 3 year old Lenovo Ideapad 100S. It did an update and then locked me out. We own 2 of these laptops and both did this. Windows is asking for a BitLocker Recovery Key. I was able to find it 1 of the laptops, but I don't have it for the other one. I'm being held hostage by Microsoft Windows 10. Help Please!

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