Hi @Reshmee Auckloo ,
As per this Documentation currently application permission is not supported for planner tasks. And because of that we can not retrieve tasks for any other user. This Graph API /users/{id}/planner/tasks
allow to retrieve tasks for current signed in user, here id
is the current signed-in user's id.
Feature request idea is already created here, you can upvote it. This forum is actively monitored by Microsoft team and make the enhancements to Microsoft Graph APIs.
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