PC端微信扫码支付成功后页面自动跳转ajax这样写哪里错了？

前端调用：
<td style="border-bottom:1px solid #ddd;padding-left:15px;background:#FAFAFA; width:445px;" height=30>订单号：<span id="HidOrderid">{$suborder.order_sn}</span></td>
.

<script type="text/javascript">
    $(document).ready(function () {
                setInterval("ajaxstatus()", 3000);    
            });
    //$("#HidOrderid").val()  为订单号码
            function ajaxstatus() {
                if ($("#HidOrderid").val() != 0) {
                    $.ajax({
                        url: "flow.php?action=GetOrder&OrderId=" + escape($("#HidOrderid").val()),//调用ashx获得订单状态
                        type: "GET",
                        dataType:"json",
                        data: "",
                        success: function (data) {
                            if (data.statues ==2) { //订单状态为1表示支付成功
                               window.location.href = "respond.php"; //页面跳转
                            }
                        },
                        error: function () {
                             alert("O No~~~"); 
                        }
                    });
                }

            } 
</script>

后台处理：
if (!empty($_REQUEST['act']) && $_REQUEST['act'] == 'GetOrder')
{

if($_GET['OrderId']){
$OrderId=$_GET['OrderId'];
$sql="select pay_status from ". $ecs->table('order_info') ." where order_sn='$OrderId' ";
$status = $db->getOne($sql);
return $status;
}
}