These telemarketers will call with no message nonstop until you dial their number back. This gives them a way around the national Do Not Call list. If you dial them back and get that 'disconnected' message it does not matter. They are free to continue to call you, DNC list or not, because they are RETURNING your call to them and the DNC list laws do not apply. On the rare occasion that a person is actually on the line when I answer I ask them to hold, push a button on my number pad to give an audible tone and then tell them that the call is being recorded and ask them to repeat their name and company. This almost always results in the calls stopping. Best option is never return a call and save it in your phone marked as spam.
They asked for me by first name. So somehow they have your identity.
I did not tell them. I asked who was calling.
They said "You are on Medicare now aren't you"?
I said none of your business and hung up.
They are probably trying to sell some sort of insurance or just scam.