Error - Using the generic type JsonResult<T> requires 1 type arguments

Hi

   I am getting error - Using the generic type JsonResult requires 1 type arguments.

public JsonResult GetCourier(string token, Int32 origin, Int32 destination)
{
    var client = new RestClient("htts://api.nimbuspost.com/v1/courier");
    client.Timeout = -1;
    var request = new RestRequest(Method.GET);
    request.AddHeader("Content-Type", "application/json");
    request.AddHeader("Authorization", "Bearer " + token);

    request.AddParameter("origin", origin, ParameterType.RequestBody);
    request.AddParameter("destination", destination, ParameterType.RequestBody);

    request.AddHeader("content-type", "application/json");
    IRestResponse response = client.Execute(request);

    Root root = JsonConvert.DeserializeObject(response.Content);
    return Json(new { status = root.status, response = root });
}

Thanks