Hi @John Kim ,
Welcome to Microsoft Q&A forum and thanks for reaching out.
By looking at the error message it seems like the error is from the http server end. I would also request you to double check if it is an intermittent issue. If so then you can try setting up retry option which would avoid this issue.
In case if the issue is consistent, then you will have check the input values for the HTTP call for the failed pipeline run and do same testing using same input data in Postman to verify if the issue is related to any of the input data for the HTTP call. And also please make sure the returned data is in expected format. You can also verify the failed HTTP response with the success response by doing a comparision.
Hope this info helps. Do let us know how it goes.
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