Invalid Audience for Resource (O365/Outlook) API

Question

So I created/registered an app. But no where in this app registration can I state that it is an outlook application. 
Otherwise, I am able to get a token but the token does not work on outlook endpoints. Need help for the error 'Invalid Audience for Resource"

{"error":{"code":"InvalidAudienceForResource", "message":"The audience claim value is invalid for current resource. Audience claim is 'api://OUR-APP-ID_SET-AS-SCOPE', request url is 'https://outlook.office.com/api/v2.0/me/messages' and resource type is 'Exchange'.", "innerError": {"requestId": "c7fe963f-a7cb-4c1f-a869-83402fdeee76","date":"2020-02-11T03:55:07}}}

I can not attached the screenshot, but will update question with screenshot once my account is verifiied. 

Answer 1

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