Credit Card Payer

My input follows the general input from this thread, yet it unnerved me that the man with barely functional English knew my credit cards (one was already canceled).  I asked for more information, what they do (trying to glean information before the usual hang up) and when I said I had NO debt, very low interest and just want to be put on the "no call" list he then hung up.  When I called the same number back - I got a confused man who had no idea what I was talking about.  There are very clever routing systems these creeps use.  UGH.  Just blocked it.