basically, i added     

AddSecurity(SecurityType.Equity, symbol, Resolution.Minute);
 AddSecurity(SecurityType.Equity, spy_symbol, Resolution.Minute);

 

and in public void OnData(TradeBars data) 

i handled uvxy, I didn't handle spy....

I think thats why it has reported the error...

 

But i dont know how to fix that... can someone give me some insights?

Best