Hi @Hari ,
Thanks for reaching out.
I am able to get the delete change notification for resource: /me/todo/lists/{taskListId}/tasks
when a task is deleted.
Response:
This issue looks like a tenant specific. I would recommend you to raise a support case with Microsoft Graph, a Support Engineer will be able to assist you better. You can raise support ticket from
http://aad.portal.azure.com/ or https://admin.microsoft.com/#/support/requests.
Hope this helps.
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