alpaca有他自己的paper账户和api。并不是用本地的paper模拟交易。

行情订阅没有买一卖一，委托不会成交

另外如果在alpaca手动下单以后不能平仓，并且会出现以下错误。求帮助。

Traceback (most recent call last):
File "c:\vnstudio\lib\site-packages\vnpy\trader\ui\widget.py", line 452, in cancel_order
self.main_engine.cancel_order(req, order.gateway_name)
File "c:\vnstudio\lib\site-packages\vnpy\app\paper_account\engine.py", line 196, in cancel_order
active_orders: Dict[str, OrderRequest] = self.active_orders[req.vt_symbol]
KeyError: 'U.SMART'