Problem From JSON to Web Services

var DataJO = [
                            {
                                LO: x;,
                                AC: "FILING FEE",
                                MAC: "",
                                amount: 500,
                            }
                       ]
            usrData = { SecurityKey: "xxx", UserToken: "567", Key: "1", Vouchers: DataJO };
            break;
    }
    var fullURL = srvURL + "/" + srvOps;
    var postData = usrData;
    $('#divresult').html("Calling: " + fullURL);
    $.post(fullURL, postData)
    .done(function(data) {
        $('#divresult').html($('#divresult').html() + "<br/>Success Result: ");
        $('#txtresult').val(JSON.stringify(data, " "));
        if (args == 'AU')
            $('#hdnToken').val(($.parseJSON(data)).UserInfo[0].UserToken);
    })
    .fail(function(msg) {
        $('#divresult').html($('#divresult').html() + "<br/>Error: ");
        $('#txtresult').val("Error: " + msg.statusText + " [Error Code: " + msg.status + "]");
    });

    return false;
}