Error on conversion to DXF about ogre HOT 4 CLOSED

    var http = new XMLHttpRequest();
    var url = "http://ogre.adc4gis.com/convertJson";
    var params = "json=" + JSON.stringify(resultAsGeojson) +
      "&skipFailures=" + true +
      "&format=" + "DXF";
    http.open("POST", url, true);
     
    //Send the proper header information along with the request
    http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
     
    http.onreadystatechange = function() {//Call a function when the state changes.
      var a;
      if(http.readyState == 4 && http.status == 200) {
            a = document.createElement('a');
            a.href = window.URL.createObjectURL(http.response);
            a.download = "test-file.zip";
            a.style.display = 'none';
            document.body.appendChild(a);
            a.click()
        }
    }

    http.responseType = 'blob';
    http.send(params);