It sounds like your Surface Book 3 is enrolled in an organization or educational institution's management system, which is preventing you from signing in with a personal account. This often happens when the device is associated with a work or school account, and the organization has set restrictions on the device.
To resolve this issue, you may need to perform a factory reset of the device to remove it from the organization's management. However, if the device is still linked to the organization's Azure Active Directory, you might not be able to bypass the sign-in requirement without the necessary credentials.
If you have access to the organization that originally managed the device, you could contact them for assistance in unblocking or releasing the device from their management. If not, consider reaching out to Microsoft Support for further guidance on how to proceed with the device.
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