The second paragraph. It cautions to watch out for scammers:
With these new security measures comes an opportunity for scammers to take advantage of unsuspecting Medicare recipients. If you are currently receiving or plan to enroll in Medicare, be particularly cautious if someone comes to your door or calls you and claims to represent Medicare. These people will claim to be representatives to gain your trust so they can steal your money, personal information, or social security number. The receipt of this new card will be automatic. You don’t have to do anything.
Got it. Thanks.