Changing closure code via API

Changing closure code via API

Hi, I've been attempting to edit the closure code via the API, specifically as part of the operation to close a request. What is the proper syntax here? The following does not work, nor does the code posted in a similar question here several years ago. This is for version 9.3 Build 9324.

{
    "operation": {
        "details": {
            "closeAccepted": "Accepted",
            "closeComment": "The closing comment",
            "closureCode": "Customer contact failure"
        }
    }
}

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