Hi ssrinivasa,
If you have sold the put, and not able to square off till expiration buying it back.. then you have no choice but to face the inevitable. For eg. if you have sold DLF PUT at 700 and collected the premium. On the day of expiry, say the stock is down to 620 and your position is still open. The real value of this put on expiray is 700-620 = 80 Rs. and you have obligation to pay. As a option seller you have OBLIGATION in hand. As option buyer, you have CHOICE in your hand. Luckily in India, options are settled in Cash so broker will debit your account by amount equal to 80*lot size of the stock.
(In US market, you would have got stocks in yr acct @ 700 and broker will debit your acct as if you have bought the stocks @700)
Options writering is risky and if one knows what they are doing then that is the place to be in options trading. Winning Options traders always write options but they manage the risk very well using other option stratagies. Naked Option writing is strictly no no for most of them.
Hope this is just a questions and not the real trade.
There are ways to adjust this trade and limit your further loss (or maybe make it profitable
provided there is enough liquidity.
Otherwise, Good luck next time.
Happy trading