Hi @Gautam Patel
I have tried this Graph API and it's working fine. Please refer to the below sample screenshot:
As you are getting 401 Unauthorized error, please make sure your token is valid. This error often means that the access token may be missing in the HTTP authenticate request header or that the token is invalid or has expired. Please refer to this documentation for more details. Please refer to this documentation for Authorization code flow.
Also, as per the contacts Graph API documentation Contacts.Read, Contacts.ReadWrite permissions (from least to most privileged) is required, please make sure you have granted these permissions before running Contacts Graph.
You can decode the token using **https://jwt.io/**and check permissions in your token.
You are getting "Invalid request, 400 Bad Request" for this
because this is not valid Graph API. Please use the valid Graph API as per the documentation.
Hope this helps.
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