Hello tim hodkin,
Thanks for reaching out!
I'm able to replicate the issue behavior. On running https://graph.microsoft.com/beta/users/<user id>?$select=signInActivity
endpoint over and over again, I'm also getting two different set of results. Please note that APIs under the /beta
version in Microsoft Graph are subject to change. Use of these APIs in production applications is not supported.
I would suggest you use List Sign-ins and Get Sign-in Graph calls. Also note that signIns involve bringing some sensitive information and hence it's restricted for users with higher privileges. A regular user might end up getting an error. Refer this known issue.
Hope this helps.
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