JSON Order Release Not Created in OTM Despite 200 OK

Summary:

Hello Everyone,

We are currently working on integrating Order Release creation into OTM using the REST API. We are submitting a JSON payload to the following endpoint using the POST method URL used https://<OTMURL>/logisticsRestApi/resources/v2/orderReleases In our request headers, we are also passing- Prefer: respond-async The expectation is that this will return a transmission number We are using Bruno (an alternative to Postman) to send the request.
Issue is - Although we consistently receive HTTP 200 OK, the Order Release is not created in OTM. There is no corresponding transmission record or order release visible in the UI.Attached the JSON payload being used for reference