An official message from Medicare:
Unfortunately, scam artists are using the coronavirus pandemic to try to steal your Medicare Number and other personal data, but you can protect yourself. If you get a call or email offering COVID-19 items like a test kit or a mask and they ask for your Medicare number, hang up or delete the email! Guard your card.
Learn more about scams and how to report suspected Medicare fraud at https://www.medicare.gov/forms-help-resources/help-fight-medicare-fraud.