Options writing premium profit

F&O
1

If I write Banknifty 32800 PE at 631 and the premium on expiry day at 3:20 pm is around 600 Rs, so has the option expired worthless?

Question 1) Do I get to keep the entire premium of 631

OR

Question 2) Will my profit be 631-600 i.e “31” rs x lot size

2

Options that expire worthless have no value, since you sold option at 631 and it expired at 600 your profit will be 31 x lot size.