Android : Android koush/ion lib unable to post and receive JSON response

I am using ION to GET/POST for REST and also to get Images into ListView but I am unable to use POST method and receive response as a JSON The ION version that I am using is 1.3.7. Tested on emulator and also on real devices 4.1.1, 4.2.2 and 4.4

Ion.with(getActivity())
    .load(URLStr)
    .addQuery("action", "dummyAction")
    .addHeader("Content-Type", "application/json")
    .setLogging("ION_VERBOSE_LOGGING", Log.VERBOSE)
    .setJsonObjectBody(jsonStr)
    .asJsonObject()
    .setCallback(new FutureCallback<JsonObject>() {
    @Override
    public void onCompleted(Exception e, JsonObject result) {
        if (null != e) {
            if (null != result) {

                Log.d(Constants.LOG_TAG, "JSON Result User basic Info: " + result);
            } else {
                Log.e(Constants.LOG_TAG, "error in posting User basic Info");
            }
        } else {
            Log.e(Constants.LOG_TAG, "error in posting User basic Info", e);
        }
    }
    });

I am getting NullPointer at result. The request JSON is also valid, and I am using GSON to construct it. The response JSON is valid as I checked it using POSTMAN chrome app.

However, below code works perfectly fine, but it's depricated ION.with(getActivity(), URL) So I dont know, where am I making mistake.

    Ion.with(getActivity(), URLStr)
            .addQuery("action", "dummyAction")
            .asJsonObject()
            .setCallback(new FutureCallback<JsonObject>() {
                @Override
                public void onCompleted(Exception e, JsonObject result) {
                    if (e != null) {

                        e.printStackTrace();
                        Toast.makeText(getActivity(), "Error loading user data", Toast.LENGTH_LONG).show();
                        return;
                    }
                    Log.d(Constants.LOG_TAG, "DATA: " + result.toString());
                    String data = result.get("status").getAsString();
                    Log.d(Constants.LOG_TAG, "DATA: " + data);
                }
            });