AUDUSD in the engulfing signal

We can see in yellow candle, its a bullish engulfing signal which I program in Pine. In this signal there is a potentially position to open, with the scenario based on Fibonacci Retracement.

Scenario
OP : 0.6834 - 0.6866 (38-50) percent
SL : 0.6811 (0) percent
TP : 0.68977 (168) percent