Azure FHIR Proxy using Postman - 401 You do not have permission to view this directory or page

I have set up an instance of Azure FHIR with an Azure FHIR proxy using this tutorial:

https://github.com/microsoft/health-architectures/tree/master/FHIR/FHIRProxy##configuration

I am unable to call the proxy without getting the following error message:

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I have created a token successfully using the following tutorial:

https://learn.microsoft.com/en-us/azure/healthcare-apis/access-fhir-postman-tutorial

I have created an app service principal in Azure with the permissions to access the FHIR proxy:

https://func-fhir-proxy-2.azurewebsites.net

I am generating the token using the following in postman:

Auth URL: https://login.microsoftonline.com/e34c8e67-182a-4085-9dc0-39a38dddea12/oauth2/authorize/?resource=https://func-fhir-proxy-2.azurewebsites.net

Access Token URL: https://login.microsoftonline.com/e34c8e67-182a-4085-9dc0-39a38dddea12/oauth2/token

Client ID: 4d138742-44c0-42cb-9878-8647a1d2ef17

Client Secret: Well..that's a secret!

Scope: openid profile

State: 12345

Postman returns 3 tokens: Access_token, Refresh_token, Id_token.

I have tried each token and all return the same 401 error.

ID token JWT looks like this:

I have tried calling the FHIR proxy API's, due to the tutorial I am not 100% which are the correct URLs:

https://func-fhir-proxy-2.azurewebsites.net/api/fhirproxy/Patient

https://fhir-test-apis.azurehealthcareapis.com/Patient/

None of this works, I just keep getting the same error. Does anyone know what I am doing wrong? Should I be calling the FHIR proxy API using the token? If so, why is the API not letting me in?

I managed to fix the issue. I found that the resource ID was needed in the auth URL:

This can be obtained from Enterprise Applications:

Also, creating two separate app registrations: