Advocacy groups recently filed a lawsuit against the Centers for Medicare & Medicaid Services. They argued that Medicare beneficiaries do not have to return money that CMS sent to them by mistake last month.

About 230,000 Medicare beneficiaries received reimbursements last month averaging $215 from CMS as a result of a computer error. The reimbursements equaled the amount of beneficiaries’ monthly premiums paid this year.

In response to the suit, CMS this week agreed to stop mailing letters that instruct beneficiaries to return the money. It also removed content on the recovery of overpayments from its Web site. The Center for Medicare Advocacy filed the suit on behalf of two consumer advocacy groups.