@Vickygggg It is late now to sell in pre open. But for next time, search for the script name in your brokers app or website.
Pre open session for IPO opens at 9 A.M. and is open upto 9:45 A.M.
Keep on watching the price upto 9:35 A.M. or so, put your sell bid 5% below that price. If your price is below the discovered price your shares will be sold in pre open..
In SME you have to sell in lots not just a few shares..
Hope this helps..