The people who are coming on here and leaving messages saying that these calls are legitimately from Discover are lying. They are part of the scam. They know people come on here and report these calls, and they are hoping you will read their messages and not suspect the true nature of their calls - which is to talk you into giving up personal info over the phone to a bunch of fat losers sitting at home trying to drum up money to buy drugs.
To report unwanted telephone calls, once you tell them to stop calling and they don't, call your district attorney and they will tell you the correct place to file a complaint for your problem. They usually have a consumer complain department for such things that you'll be directed to on the phone. Know your rights!
I have had a call from them it is Discover I had applied for a loan and called them to finalize there were problems and the lady called back with some solutions. The call type is none of the ones they list.