` def on_trade(self, trade: TradeData):
        """
        Callback of new trade data update.
        """
        msg = ["trade >>> ", trade.datetime, trade.symbol, trade.orderid, trade.tradeid, trade.direction, trade.offset, trade.price, trade.volume]
        self.write_log("\t".join([str(x) for x in msg]))
        self.write_log(self.bullorder)
        self.write_log(self.bearorder)
    # 处理开多
    if trade.direction.value ==  Direction.LONG.value and trade.offset.value == "开":
        self.bullorder["status"] = "POS"
        self.bullorder["trade_time"] = trade.datetime
        # 多单止盈
        self.write_log("=========================================bull止盈================================================")
        self.sell(self.bullorder["takeprofit_price"], 1)
        # 多单止损
        self.write_log("=========================================bull止损================================================")
        self.sell(self.bullorder["stoploss_price"], 1)`
如代码, 在on_trade中挂止盈止损, 但是只有前面的止盈可以委托成功, 止损并未发出, 为啥?
然后再高频中应该怎样现价止损?
