Comment on STT Trap - Options Expiry - NSE BSE MCX-SX
If you see the settlement price of Bank nifty NOV it is 10906 (see the future closing). Since the closing is higher than 10900 all 10900 puts are Out of money even though the last traded price might be 15.9. Since it is OTM it expires worthless (zero and not 0.05).
Hope this clarifies