@Bryan Trochessett, Thanks for posting in Q&A. From your description, it seems you have questions about Microsoft 365 business account login issue which we are not familiar.
I have done some researching. Maybe you can do Microsoft Entra join to let the account login. You can join during OOBE.
https://learn.microsoft.com/en-us/entra/identity/devices/device-join-out-of-box
Or you can add your work or school account via Settings > Accounts > Add a Work or School Account1, click "Connect", then "Join the device into Azure Active Directory"
.
However, if it's not working, you can go to Microsoft 365 community to get more help.
Hope the above information can help.
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