It simply just returned no response!

My code looks like this, please help!

public static string GetJasonFromAPI(string querytext)
{

        unirest_net.http.HttpResponse<MyClass.RootObject> jsonResponse = Unirest.get("https://twinword-language-scoring.p.mashape.com/text/?text=" + querytext)
        .header("X-Mashape-Key", "6eeAh2lHw7mshDvcFf3ZkKBeqIBBp1fZgVcjsnSsZBzNg5RjSz")
        .header("Accept", "application/json").asJson<MyClass.RootObject>();


        var myBody = jsonResponse.Body;

        return myBody.ToString();
    }

    public class MyClass
    {
        public class Result
        {
            public string ten_degree { get; set; }
            public string value { get; set; }
            public string version { get; set; }
            public string author { get; set; }
            public string email { get; set; }
            public string result_code { get; set; }
            public string result_msg { get; set; }
        }

        public class RootObject
        {
            public List<Result> results { get; set; }
        }
    }