Hey Johnny, check this article and steps for verifying the registration process of the users - https://learn.microsoft.com/en-us/azure/active-directory/authentication/howto-authentication-methods-activity
Also you check via API - https://learn.microsoft.com/en-us/graph/api/resources/azure-ad-auditlog-overview?view=graph-rest-1.0
Hope this helps.
JS
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