Hello @Abhay Chandramouli,
Thanks for reaching out!
When you specify $select=signInActivity
or $filter=signInActivity
while listing users you will get the SignInActivity property. You can also use https://graph.microsoft.com/v1.0/users/{user-id}?$select=signInActivity,displayName
API to get the signInActivity of a particular user. Please refer the below screenshot:
Also, make sure AuditLog.Read.All permission is consented to get signInActivity details.
Hope this helps.
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