It might still be getting lost in translation.
You will need to change your login Password / Pin to your NExT UID ( what you get when you scan your NExT on your KBR1)
Where it says “Enter your password”
Enter your current password
In the text field where it says “Enter your new password”
Scan your NExT on the KBR1 Reader
In the text field where it says “Re-enter your new password”
Scan your NExT on the KBR1 Reader
Microsoft will send you a new code to change your password through the phone number that is associated with your account.
Follow the guide below if you get stuck
If it still doesn’t work, In step number 5, try choosing PIN rather than PASSWORD.
Remember to make a copy of your PIN ( UID from NExT )
Maybe try setting up a guest account on your computer first as a test 