Here is the screenshot of the future contract payoff simulator which is simply wrong as it is showing even after shortselling the contract there is profit , which is not true.
The entry price in the input box is 21801, you have hovered on the pay-off @ 21680, hence the probable P&L will be positive, as it is a short position. You make money when market goes down for short position.
I don’t find any issue in this. Let me know if I am wrong or missing out something.