I use this URL to get id_token:
https://login.microsoftonline.com/common/oauth2/authorize?
response_type=id_token%20code&
client_id=MY_CLIENT_GUID_ID_IN_
I had this issue today when I was playing with graph API, the problem in my case was how I was generating the token.
I used postman for generating the token wherein the Auth URL section I was adding the resource = client_id whereas it should be the graph URL. After making that change I was able to make the call via postman.
In order for the above to work, please make sure your application in Azure has delegated permissions to access the Graph API.