Some scum low life with an Indian accent who gave me a name then said he was from Medicare services. He then asked how was I today and I replied "not very good - you interrupted me." Then I hung up. Scam with phony CID.
If they claim to be from Medicare Service and you are on Medicare, ask them what name they're looking for. If they happen to have your actual name, then ask them to provide your ID number. Chance are they are scammers and will not have such a number.
Medicare will contact you by actual mail delivered by the mailman. Any outfit selling "services" or "supplement insurance" by cold calling is absolutely a scam since that activity is illegal.