MVC :: Not Getting Value From Json

I have written a code that go to controller using json and get the date from controller. Every thing works fine when running locally, but when i deploy my application to server, i am not getting the data returned from controller using jsonreturn. One more thing My firewall has blocked the GET. So how to resolve this.

//On Page
var URL = "/Home/AsyncGetCheapestList/" + param;
$.getJSON(URL, null, function(data) {
// displaying data content ;
});
//On controller
public JsonResult SetServiceIdServiceName(string asyncInputs)
{
List<string> st = new List<string>();
st.Add("one");
st.Add("two");
st.Add("three");
st.Add("four");
return Json(st,JsonRequestBehavior.AllowGet );
}

Here GET is blocked by my firewall so unable to get the data. Is that any other way to get it.