Hello @chris mitchell !
Hope you are having a great day!
Thank you for asking a Question! We are Glad to Assist you!.
I believe you are seeing the 8-digit code on your Authenticator App because the Passwordless signing is enabled for your Microsoft account (personal Microsoft account).
You can identify the same by looking for a key symbol listed on the top of your account in the Authenticator App profile.
I would suggest you to take a look at the steps mentioned here and see if this helps:
Let me know if the above solution resolved your issue!
Regards,
Tasadduq Burney
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