What is wrong with this deserialization? Keep getting error trying to deserialize the response file

What is wrong with this deserialization of my response file?
I Keep getting exception when I am trying to deserialize the response file to my model that I created.
When I try to put the response json in a file and run the deserialize it works fine. But when I am trying to convert the result it keeps failing.
What am I doing wrong?

HttpResponseMessage response = client.GetAsync(URL+pg.urlParameters).Result;  
if (response.IsSuccessStatusCode)
{

    var result = response.Content.ReadAsStringAsync();

    var detailsList = Newtonsoft.Json.JsonConvert.DeserializeObject<Rootobject>(result.ToString());

I get an exception as
Newtonsoft.Json.JsonReaderException: ‘Unexpected character encountered while parsing value: S. Path ”, line 0, position 0.’

>Solution :

You forgot to put the ‘await’ keyword. So your result is a Task and not the actual result yet. This should fix it:

if (response.IsSuccessStatusCode)
    {

        var result = await response.Content.ReadAsStringAsync();

        var detailsList = Newtonsoft.Json.JsonConvert.DeserializeObject<Rootobject>(result);