PaulD.86794 (Customer) asked a question.
Client authentication to token endpoint using private_key_jwt "failing with invalid_request (Cannot supply multiple client credentials"
I have added an Oauth 2 client app using the api. I have included a public key that corresponds to the private key that is used to generate the client assertion. From my traces I can see the POST to the token endpoint which includes the client assertion in the body. I don't see any other credentials in the header of the request. Yet I still received the response "Cannot supply multiple client credentials. Use one of the following: credentials in the Authorization header, credentials in the post body, or a client_assertion in the post body".
Any clues about how to troubleshoot this?
Hello Paul,
Depending on your method of doing the request something might be appending your client in the authorization header, as it's most common.
Try using Postman to test the flow, and then once you can determine if the flow is working as expected, we will know if the issue is with the flow itself or the implementation and how it composes the POST on the /token endpoint.
As it would be hard to provide assistance via the Discussions board, please open a support ticket and send the trace of the POST on the /token endpoint so we can help you debug the flow.
Thank you,
Bogdan Andrisan
Developer Support Engineer