I called 18001600 and they asked me to call smartbuy customer care and then I called them. They said it is a HDFC Bank offer and you should contact them. Again I called the same hdfc customer care and they given one more toll free number and mail ID. Toll free number is not working. Dropped mail and waiting.
@mayankcse10 By the way, may I know which number you contacted to raise compliant?