使用支付宝，报错ALI38173。急急急

function Pay() {
plus.nativeUI.showWaiting();
mui.ajax(url + '/xxx/xxx', {
data: {

                },  
                type: "post",  
                dataType: "json",  
                headers: {  
                    'Content-Type': 'application/json'  
                },  
                success: function(data) {  
                    plus.nativeUI.closeWaiting();  
                    if(data.code == 0) {  
                        alert(data.msg);  
                        var order= data.msg;  
                        plus.payment.request(channel, order, function(result) {  
                            plus.nativeUI.alert("支付成功！", function() {  
                                //back();  
                            });  
                        }, function(error) {  
                            plus.nativeUI.alert("支付失败：" + error.code);  
                        });  
                    } else {  
                        plus.nativeUI.alert("下单失败");  
                    }  
                },  
                error: function() {  
                    plus.nativeUI.closeWaiting();  
                    plus.nativeUI.alert("系统错误");  
                }  
            });  
        }  

order：app_id=2017****23&biz_content=%7b%22body%22%3a%22%e6%88%91%e6%98%af%e6%b5%8b%e8%af%95%e6%95%b0%e6%8d%ae%22%2c%22out_trade_no%22%3a%22sadfa20170316155320841%22%2c%22product_code%22%3a%22QUICK_MSECURITY_PAY%22%2c%22subject%22%3a%22App%e6%94%af%e4%bb%98%e6%b5%8b%e8%af%95DoNet%22%2c%22total_amount%22%3a%220.01%22%7d&charset=UTF-8&format=json&method=alipay.trade.app.pay&notify_url=http%3a%2f%2fnotify.jazzweng.com%2fNotifyUrl%2fAlipayNotifyUrl.aspx&sign_type=RSA&timestamp=2017-03-16+15%3a53%3a20&version=1.0&sign=H7XfY91nDMxGEDux6Xmyuo61e5%2fL5wCJsU9iz7IuhXf6WmNXWY5%2bJtHJu6WjiGQr63tFutKrKhiqSh39574f%2bFSh0VyA6vvk27T9H9G9bYRM5UZuDcNiLbfi21jlVhV%2bdqs9d6YeuLamJpNrWuOo2%2fk6vtoLFiXYOjkKfIe%2b2eo%3d

请求参数是没有问题的；已经跟支付技术对接过，他那边拿我的请求参数是可以进行支付的。但是我使用我们的方法进行支付一直报ALI38173错误；是什么原因呢？？？