No-transactions-coming-in-Strategy-Monitor-for-external-symbols

Following code attempts to buy stock1 or stock2 based on the strategy setting's single symbol and some parameters - using 1min scale. Backtest returns correct results. When used in strategy monitor as auto-trade, there is no transaction coming through. Order manager shows no attempt to place any order by SM. I have tried using Dummybroker, TDA and IB without luck. Is there any special consideration for auto-trading trading stock symbols other than the strategy setting's?

thank you

CODE:
        public override void Execute(BarHistory bars, int idx)
        {
         int index = idx;
         Position foundPosition1 = FindOpenPositionAllSymbols(1);
         Position foundPosition2 = FindOpenPositionAllSymbols(2);

         if (foundPosition1 == null && foundPosition2 == null)
         {
            if(bars.DateTimes[index].GetTime() <= Parameters[2].AsInt)
            {
               if (indicator[index] >= Parameters[0].AsDouble)
               {
                  _transaction = PlaceTrade(stock1, TransactionType.Buy, OrderType.Market, 0, 1, $"Buy " + Symbol1);
               }
               if (indicator3[index] >= Parameters[0].AsDouble)
               {
                  _transaction = PlaceTrade(stock2, TransactionType.Buy, OrderType.Market, 0, 2, $"Buy " + Symbol2);
               }
            }
         }