IBGateway: 981

I met below timeout while doing live trading

ERROR:: BrokerageSetupHandler.LoadExistingHoldingsAndOrders():  System.TimeoutException: InteractiveBrokersBrokerage.GetOpenOrders(): Operation took longer than 15 seconds.

I tried to increasing waiting time, but not work.

The error occurred at below line

    _client.ClientSocket.reqOpenOrders();

could any one  give me a hand?