The Risk & Reward ratio should show number similar to 1:3
meaning it will calculate how much the stop loss is, and how much the take profit or closed trade value. Then display a ratio 1:2, 1:3, 1: 4, ect...
If no value of stop loss is entered in the trade, then it will display N/A
I've attached a picture to show you where to add Risk & Reward ratio for each trade.
I trade Forex using my Bollinger Trend PRO mt4 indicator.