Hi Vimal, gcn promo is a scam. As you have already sent them some details about you, please go immediately to the local police and tell them what you have sent off. If you have given out any bank details on the "claim form" then you are probably about to be ripped off already. Don't reply to emails saying you have won a lottery, you haven't.
YOU CANNOT WIN A LOTTERY UNLESS YOU BUY A TICKET. You cannot enter a lottery by giving your phone number, or by having an email address or anything else. The law in England governs all gaming and lotteries, and states that you cannot enter a competition which pays a cash prize unless you buy a ticket. You didn't buy a ticket, therefore you are not going to win any money.
My advice would be to change your email address, and get some advice on incoming spam mail from someone you know and trust. Don't send off any more details about yourself, and good luck.