td.ReqQryClassifiedInstrument查询不到新品种

您好，
请问td.ReqQryClassifiedInstrument为什么查询不到最新上市的品种？比如原木lg和多晶硅ps？

```
field = tdapi.CThostFtdcQryClassifiedInstrumentField()
field.InstrumentID = contract # 这里填lg,LG,ps,PS, 都找不到。最新的可以找到的品种是瓶片PR
field.ExchangeID = ''
field.TradingType = tdapi.THOST_FTDC_TD_ALL
field.ClassType = tdapi.THOST_FTDC_INS_FUTURE

td.ReqQryClassifiedInstrument(field, reqid)

```