ICICI Bank — fraud call for lapsed reward points

I received a call on 23/09/17 17:15 hrs from a lady saying that she is from icici bank credit card department and they want to redeem my lapsed reward points. She was looking a real professional employee and started asking about the credit card details. I answered with credit card number, expiry date and brand of credit card. Then she asked about the cvv number by asking the level of card. She was saying that "turn your card and tell me the 7 digit completely, which is your card level". That time i realised that it is a fraud call. Then she told i will receive a confirmation sms and i have to tell the reference number in that to a senior rep, who will call me later on for final confirmation. I stopped the call there.
Number is : [protected]