HDFC is one of India’s Largest Bank, which continue to be a major portion of the banking service of Indians. There are numerous services that are being provided to customers through their accounts, debit card and credit card services. Enable/Disable Online Transaction in HDFC Debit Card In the past, customers had to swipe their HDFC debit card for any payment or to make any transaction. in present days the online transactions are being used everywhere. Customers have to provide their debit card number and the CVV number to submit for the online transaction.