Call 1-800-MEDICARE (1-800-633-4227).TTY users can call 1-877-486-2048. There might be a problem that needs to be corrected, like updating your mailing address.
Sign in to your MyMedicare.gov account. If you don’t have an account yet, visit MyMedicare.gov to create one. You can sign in to see your Medicare Number or print an official copy of your card.