This error in the console while backtesting is driving me batty!  I get quite a few of the following errors in the console when I backtest:

Backtest Handled Error: The security with symbol 'NWSA T3MO1488O0H1' is marked as non-tradable.

I have the following block in my portfolio code to try and handle it right when it creates the target to hand off to execute:

if (algorithm.Securities[insight.Symbol].IsTradable) {
Decimal numberOfShares = algorithm.CalculateOrderQuantity(insight.Symbol, .10m);
targets.Add(new PortfolioTarget(insight.Symbol, numberOfShares));
}

What am I missing?  I am checking literally as I am making the trade, I looked at the open source code and it looks like I am using the same check that is used a bit down the line to throw the error.