Phishing scam

I get calls from Card Member Services at least 3-4 times a month.  I have tried pushing 2 as the call indicates to be removed but in a few days they call again.  Finally when they called I spoke to a rep. I was asked all kinds of personal info, most of whick I declined to answer since if they were legitimate they would have that info.  When I asked for them to give me the info they had and I would verify if it was correct, they hung up on me.