diff --git a/Binance.TradeRobot.Business/Business/TradeBusiness/D21TradeBusiness.cs b/Binance.TradeRobot.Business/Business/TradeBusiness/D21TradeBusiness.cs
index 1a47caa..9d04074 100644
--- a/Binance.TradeRobot.Business/Business/TradeBusiness/D21TradeBusiness.cs
+++ b/Binance.TradeRobot.Business/Business/TradeBusiness/D21TradeBusiness.cs
@@ -146,7 +146,7 @@ namespace Binance.TradeRobot.Business
 
                 if (balance < previewTradeAmount)
                 {
-                    #region 验证借币比例
+                    #region 验证借币
                     step = "验证借币";
                     diffAmount = previewTradeAmount - balance;
                     var diffRatio = diffAmount / balance * 100;     //借币比例
@@ -226,7 +226,31 @@ namespace Binance.TradeRobot.Business
                 #endregion
 
                 #region 下单
+                step = "下单";
+                var orderId = apiClient.IsolatedMarginPlaceOrder(robot.Symbol,
+                                                                 Enums.TradeDirection.Buy,
+                                                                 Enums.OrderType.MARKET,
+                                                                 quoteAmount: previewTradeAmount);
+                var buyOrder = new SpotOrder()
+                {
+                    Id = orderId,
+                    CreateTime = DateTime.Now,
+                    ExchangeId = robot.ExchangeId,
+                    LoanAmount = diffAmount,
+                    OrderType = Enums.OrderType.MARKET,
+                    PolicyType = Enums.TradePolicy.D21,
+                    RobotId = robot.Id,
+                    State = Enums.SpotOrderState.Created,
+                    Symbol = robot.Symbol,
+                    TradeDirection = Enums.TradeDirection.Buy
+                };
 
+                fsql.Transaction(() =>
+                {
+                    fsql.Insert(buyOrder).ExecuteAffrows();
+                    if (previewTradeAmount != d21Robot.D21Policy.Position)   //借币失败 仓位减少
+                        fsql.Update<D21Policy>(d21Robot.D21Policy.Id).Set(d => d.Position, previewTradeAmount).ExecuteAffrows();
+                });
                 #endregion
 
             }
diff --git a/SDKAdapter/APIClient/BaseAPIClient.cs b/SDKAdapter/APIClient/BaseAPIClient.cs
index 8dce4ee..00a142a 100644
--- a/SDKAdapter/APIClient/BaseAPIClient.cs
+++ b/SDKAdapter/APIClient/BaseAPIClient.cs
@@ -84,11 +84,11 @@ namespace SDKAdapter.APIClient
         public virtual long IsolatedMarginPlaceOrder(string symbol,
                                                      Enums.TradeDirection tradeDirection,
                                                      Enums.OrderType orderType,
-                                                     decimal? quantity,
-                                                     decimal? quoteAmount,
-                                                     decimal? price,
-                                                     decimal? stopPrice,
-                                                     string newClientOrderId)
+                                                     decimal? quantity = null,
+                                                     decimal? quoteAmount = null,
+                                                     decimal? price = null,
+                                                     decimal? stopPrice = null,
+                                                     string newClientOrderId = "")
         {
             throw new NotImplementedException();
         }
diff --git a/SDKAdapter/APIClient/BinanceAPIClient.cs b/SDKAdapter/APIClient/BinanceAPIClient.cs
index faa36ad..a16a1a2 100644
--- a/SDKAdapter/APIClient/BinanceAPIClient.cs
+++ b/SDKAdapter/APIClient/BinanceAPIClient.cs
@@ -107,11 +107,11 @@ namespace SDKAdapter.APIClient
         public override long IsolatedMarginPlaceOrder(string symbol,
                                                       Enums.TradeDirection tradeDirection,
                                                       Enums.OrderType orderType,
-                                                      decimal? quantity,
-                                                      decimal? quoteAmount,
-                                                      decimal? price,
-                                                      decimal? stopPrice,
-                                                      string newClientOrderId)
+                                                      decimal? quantity = null,
+                                                      decimal? quoteAmount = null,
+                                                      decimal? price = null,
+                                                      decimal? stopPrice = null,
+                                                      string newClientOrderId = "")
         {
             var binanceOrderSite = (Binance.Net.Enums.OrderSide)(int)tradeDirection;
             var binanceOrderType = (Binance.Net.Enums.SpotOrderType)(int)orderType;