@ScottM This can happen either due to Security Defaults or Azure AD Identity Protection feature.
- For Security Defaults, navigate to:
Azure Active Directory > User settings > User feature previews > and check if Users can use preview features for registering and managing security info – enhanced is enabled.
- For Azure AD Identity protection, navigate to:
Azure AD Identity protection > MFA Registration Policy > check whether the policy is enforced and user is assigned to the policy.
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