Hello @Sree S V
Thanks for reaching out!
It seems that you are using delegated permissions to access users/{user-id}/events endpoint. For accessing this API, you require an application token. Refer this document to know more about it. Please make sure that your app has been granted the Calendars.Read
application permission to list/read the events of a particular user. Alternatively, you can test the users/{user-id}/events API in Postman with Calendars.Read application permission granted to your Azure App.
Please refer this access scenarios document for more details.
Hope this helps.
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