Unable to use HdinsightKafka REST proxy API after authenticating with access token.

@AwesomePaul - Thanks for the question and using MS Q&A platform.

First, it's important to note that the REST proxy endpoint requires an OAuth token for authentication. You mentioned that you were able to authenticate the endpoint, but it's possible that there was an issue with the token or the authentication process.

To troubleshoot this issue, I would recommend checking the following:

• Make sure that the OAuth token you're using is valid and has the necessary permissions to access the Kafka cluster. You can check this by decoding the token and verifying the claims.
• Check the REST API reference to ensure that you're using the correct endpoints and parameters for the operations you're trying to perform. You can find the reference here: https://docs.microsoft.com/rest/api/hdinsight-kafka-rest-proxy/
• Verify that the Kafka cluster is running and accessible. You can do this by using a Kafka client to connect to the cluster directly.

If you've checked these items and are still having issues, it's possible that there's an issue with the Kafka cluster or the REST proxy endpoint. In this case, I would recommend opening a support ticket for further assistance.

Hope this helps. Do let us know if you any further queries.

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