Ajax post returning error

Ajax post returning error

Im having the following ajax cal in my JS file in Durundal ,
var dataJSON ={ID : "jo"};
self.js = $.ajax({
type: "POST",
dataType: String,
url: "http://localhost:53081/api/File",
data: JSON.stringify(dataJSON),
error: function (xhr, status, error) {
alert(status);
},
success: function (json) {
alert("Data Returned: " + JSON.stringify(json));
}
});
and my REST api is
[HttpPost]
public string upload(string ID)
{
string givenId = ID;
return givenId;
}
but when i call thsi methos im simply getting error alert . what went wrong