As per the error message/code: AADSTS500011, the resource principal was not found in the tenant. That means Microsoft Entra access token generated via https://login.microsoftonline.com/{{tenantid}}/oauth2/token was not matching with the tenant that FHIR is located.
- Decode the token generated in the Postman via https://jwt.ms and check if
tid
value i.e., Tenant ID, is correct. - Compare the
TID
with tenant id of the subscription for the health care workspace in the azure portal and check if both the IDs matches.