Traceback (most recent call last):
File "E:\Software Installation\vnpy-2.0.7\vnpy-2.0.7\vnpy\trader\ui\widget.py", line 858, in send_order
self.main_engine.send_order(req, gateway_name)
File "E:\Software Installation\vnpy-2.0.7\vnpy-2.0.7\vnpy\app\risk_manager\engine.py", line 58, in send_order
return self._send_order(req, gateway_name)
File "E:\Software Installation\vnpy-2.0.7\vnpy-2.0.7\vnpy\trader\engine.py", line 186, in send_order
return gateway.send_order(req)
File "E:\Software Installation\vnpy-2.0.7\vnpy-2.0.7\vnpy\gateway\ctp\ctp_gateway.py", line 174, in send_order
return self.td_api.send_order(req)
File "E:\Software Installation\vnpy-2.0.7\vnpy-2.0.7\vnpy\gateway\ctp\ctp_gateway.py", line 755, in send_order
self.reqOrderInsert(ctp_req, self.reqid)
ValueError: Cannot convert empty string to a character
