“System.Net.WebException”类型的未经处理的异常在 aliyun-net-sdk-core.dll 中发生

报错在for循环那里，差不多循环821次的时候报错：“System.Net.WebException”类型的未经处理的异常在 aliyun-net-sdk-core.dll 中发生   其他信息: 请求被中止: 操作超时。我点击了继续以后才继续循环，这是为什么？


using Aliyun.Acs.Core;
using Aliyun.Acs.Core.Exceptions;
using Aliyun.Acs.Core.Profile;
using Aliyun.Acs.Push.Model.V20160801;
using System;


namespace AlibabaCloud
{
    public class Push
    {
        static void Main()
        {
            IClientProfile clientProfile = DefaultProfile.GetProfile("cn-hangzhou", "我的ID", "我的key");
            DefaultAcsClient client = new DefaultAcsClient(clientProfile);
            PushRequest request = new PushRequest();


            // 推送目标
            request.AppKey = 24577343;
            //推送目标: DEVICE:按设备推送 ALIAS : 按别名推送 ACCOUNT:按帐号推送  TAG:按标签推送; ALL: 广播推送
            request.Target = "ALL";
            //根据Target来设定，如Target=DEVICE, 则对应的值为 设备id1,设备id2. 多个值使用逗号分隔.(帐号与设备有一次最多100个的限制)
            request.TargetValue = "all";
            //消息类型 MESSAGE NOTICE
            request.PushType = "NOTICE";
            //设备类型 ANDROID iOS ALL.
            request.DeviceType = "ANDROID";
            // 消息的标题
            request.Title = "a";


            #region 推送配置: iOS
            //推送配置: iOS
            // iOS应用图标右上角角标
            request.IOSBadge = 50;
            //开启静默通知
            request.IOSSilentNotification = false;
            // iOS通知声音
            request.IOSMusic = "default";
            //iOS10通知副标题的内容
            request.IOSSubtitle = "iOS10 subtitle";
            //指定iOS10通知Category
            request.IOSNotificationCategory = "iOS10 Notification Category";
            //是否允许扩展iOS通知内容
            request.IOSMutableContent = true;
            //iOS的通知是通过APNs中心来发送的，需要填写对应的环境信息。"DEV" : 表示开发环境 "PRODUCT" : 表示生产环境
            request.IOSApnsEnv = "DEV";
            //消息推送时设备不在线（既与移动推送的服务端的长连接通道不通），则这条推送会做为通知，通过苹果的APNs通道送达一次。注意：离线消息转通知仅适用于生产环境
            request.IOSRemind = true;
            //iOS消息转通知时使用的iOS通知内容，仅当iOSApnsEnv=PRODUCT && iOSRemind为true时有效
            request.IOSRemindBody = "iOSRemindBody";
            //自定义的kv结构,开发者扩展用 针对iOS设备
            request.IOSExtParameters = "{\"key1\":\"value1\"}";
            #endregion




            #region 推送配置: Android
            // 推送配置: Android
            // 通知的提醒方式 "VIBRATE" : 震动  "SOUND" : 声音  "BOTH" : 声音和震动  NONE : 静音
            request.AndroidNotifyType = "BOTH";
            //通知栏自定义样式0-100
            request.AndroidNotificationBarType = 1;
            //通知栏显示优先级
            request.AndroidNotificationBarPriority = 0;
            //点击通知后动作 "APPLICATION" : 打开应用 "ACTIVITY" : 打开AndroidActivity "URL" : 打开URL "NONE" : 无跳转
            request.AndroidOpenType = "APPLICATION";
            //Android收到推送后打开对应的url,仅当AndroidOpenType="URL"有效
            request.AndroidOpenUrl = "http://www.baidu.com";
            //设定通知打开的activity，仅当AndroidOpenType="Activity"有效
            request.AndroidActivity = "com.hz.aliyundemo";
            //Android通知音乐
            request.AndroidMusic = "default";
            //设置该参数后启动小米托管弹窗功能，此处指定通知点击后跳转的Activity（托管弹窗的前提条件：1. 继承小米辅助通道；2. storeOffline设为true)
            //request.AndroidXiaoMiActivity = "com.ali.demo.MiActivity";
            //小米弹窗标题
            //request.AndroidXiaoMiNotifyTitle = "Mi Title";
            //小米弹窗内容
            //request.AndroidXiaoMiNotifyBody = "MiActivity Body";
            // 设定android类型设备通知的扩展属性
            //request.AndroidExtParameters = "{\"k1\":\"android\",\"k2\":\"v2\"}";
            #endregion
            #region 推送控制
            // 推送控制
            String pushTime = DateTime.UtcNow.AddSeconds(3).ToString("yyyy-MM-ddTHH\\:mm\\:ssZ");
            request.PushTime = pushTime;//延迟3秒发送
            String expireTime = DateTime.UtcNow.AddDays(2).ToString("yyyy-MM-ddTHH\\:mm\\:ssZ");
            request.ExpireTime = expireTime;//设置过期时间为2天
            request.StoreOffline = false;
            #endregion
            try
            {
                for (int i = 1; i <= 500; i++)
                {
                    // 消息的内容
                    request.Body = "您的验证码为（1），请于【2】内正确输入，如非本人操作，请忽略此短信。一语成谶，魑魅魍魉！ABCdef" + Convert.ToString(i);
                    client.GetAcsResponse(request);
                }
                Console.ReadLine();
            }
            catch (ServerException e)
            {
                Console.WriteLine(e.ErrorCode);
                Console.WriteLine(e.ErrorMessage);
                Console.ReadLine();
            }
            catch (ClientException e)
            {
                Console.WriteLine(e.ErrorCode);
                Console.WriteLine(e.ErrorMessage);
                Console.ReadLine();
            }
        }
    }
}