Question: I keep getting error messages suggesting that a resident’s Medicare Beneficiary Identifier (MBI) is incorrect. What might I be doing wrong? Texas Subscriber Answer: The Centers for Medicare & Medicaid Services (CMS) explains that a Medicare beneficiary’s MBI may change. “If you get an eligibility transaction error code (AAA 72) of ‘invalid member ID,’ or ‘The beneficiary you requested cannot be found. Please verify your information,’ your patient’s MBI may have changed” since it was originally issued, CMS says. “Remember, requests to change MBIs can occur if a Medicare beneficiary, their authorized representative, or CMS suspects a number is compromised.” Residents, their families, or representatives may give you the old card or be admitted to your facility before receiving the new card. Do this: If you get such an error code, “do a historic eligibility search to get the termination date of the old MBI,” CMS advises. Then, “get the new MBI from your Medicare Administrative Contractor’s secure lookup tool.”