BEWARE- ASKING FOR VERY PERSONAL DETAILS

I got a call from an agent saying I was nominated by a friend to receive a free gift. However, in order to receive this free gift, I had to answer a series of invasive questions. E.g, where I work, what I do, whether or not I have a credit card. Once they asked me who I banked with, my banking details and ID number, I told the consultant I would rather not proceed as I am uncomfortable with all the personal questions they are asking. She kept saying its for marketing purposes. How is knowing my banking details & ID number for marketing purposes? They can keep their gifts. Thanks. BEWARE.