At present following types of Debit card Bank is issuing:
i. PIN based Debit Card (Maestro card)
ii. Signature based Classic Debit card (Master card)
iii. Signature based Gold Debit card with photo (Master card)
iv. PNB Platinum Debit Card
v. Mitra ATM Card
Where Maestro card has no CVV number and expiry date. It has only valid from date. Hence it can't be used in ecommerce transaction. If you have maestro card then ou have to upgrade it to the mastercard. For this you have to block your current card by calling PNB customer care at 18001802222(Toll free Any Network). Then you have to go to the nearest PNB branch and fill the debit card form. They will give you new card with mastercard logo with it. And in the reverse of the card from the 7 digit number last 3 digit is your CVV number.