ServiceDesk API V3 - Update a Request

ServiceDesk API V3 - Update a Request

Can anyone help with this simple attempt to update a Request using the v3 API syntax?  I am currently using PostMan to test the API and can generate AuthTokens, Retrieve a list of Requests, and Create a Request, Retrieve the newly created request.  However, I have been unable to get a simple update to work.

REQUEST HEADERS:

Accept:application/vnd.manageengine.sdp.v3+json
Authorization: {{AUTHTOKEN}} <<==POPULATED FROM POSTMAN VARIABLE
Content-Type:application/x-www-form-urlencoded

BODY:
input_data= {
"request": {
"category": {
"name": "DOCUMENTATION"
}
}
}

RESPONSE:
{
    "response_status": {
        "status_code": 4000,
        "messages": [
            {
                "status_code": 4001,
                "field": "id",
                "type": "failed"
            }
        ],
        "status": "failed"
    }
}

The same update works using the version 1 syntax.

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