Historical API too many requests

Histrorical API giving me "too many request" error.
Can you please tell me no of simultaneous request that i can send ?

Exception : {\"ClassName\":\"KiteConnect.NetworkException\",\"Message\":\"Too many requests\",\"Data\":null,\"InnerException\":null,\"HelpURL\":null,\"StackTraceString\":\" at KiteConnect.Kite.Request(String Route, String Method, Dictionary`2 Params)\\r\\n at KiteConnect.Kite.GetHistoricalData(String InstrumentToken, DateTime FromDate, DateTime ToDate, String Interval, Boolean Continuous)\\r\\n at Kite.AutoTrading.Business.Brokers.ZerodhaBroker.GetData(Symbol symbol, String period, DateTime fromDate, DateTime toDate, Boolean isContinous) in C:\\\\Users\\\\sagar.raut\\\\source\\\\repos\\\\Kite.AutoTrading\\\\Kite.AutoTrading.Broker\\\\ZerodhaBroker.cs:line 42\",\"RemoteStackTraceString\":null,\"RemoteStackIndex\":0,\"ExceptionMethod\":\"8\\nRequest\\nKiteConnect, Version=3.0.0.0, Culture=neutral, PublicKeyToken=null\\nKiteConnect.Kite\\nSystem.Object Request(System.String, System.String, System.Collections.Generic.Dictionary`2[System.String,System.Object])\",\"HResult\":-2146233088,\"Source\":\"KiteConnect\",\"WatsonBuckets\":null}