HDFC Bank — Getting too many calls from hdfc bank for personal loans

This is disgusting, getting too many calls from hdfc bank and their consultancies for personal loans. Hope you can understand how they are irritating. I didn't apply for loan/credit cards in any hdfc site nowhere. Couldn't understand how bank got my numbers.
One of your tele caller said that calls are coming from different branches. I said that banks have centralized software then she cut the phone.
Please take it seriously otherwise i am going to take police action.