Ted is not only tired of Robocalling, but he's concerned about everything that they know about him. Leo says that can be frightening, especially when criminals prey on older users who make them believe they're from Medicare. They take advantage of public information that can be found online and use it to suck you in. Some of it is also from security breaches that are then sold on the dark web. It's highly illegal. What Leo advises is to ask them for a number and you will call them back. Then call Medicare directly and ask. Chances are, you're not getting MediCare, but some scammers.
What can be done about it? Leo says not much sadly. It's like playing a game of whack-a-mole. You can add your number to a DoNotCall list, and there's a new technology called Shaken and Stir, which has promise. But the thing is that some voiceover internet companies aren't required to use it, so scammers end up using them and skirting the system.
Know that the Government won't call you. IRS, Medicare, etc. They don't call. They mail. Do not give out any personal information or credit card numbers over the phone to anyone. And don't answer any call from a number you don't recognize.