MINNEAPOLIS — Minnesota’s Department of Human Services fails to adequately verify the eligibility of people who enroll in public health care programs through MNsure, the state’s health insurance exchange, the state’s legislative auditor reported Wednesday.

The Office of the Legislative Auditor found several instances where the department paid for benefits to people enrolled in Medical Assistance and MinnesotaCare who weren’t eligible because their incomes were too high or other errors.

The agency also found that DHS failed to bill MinnesotaCare recipients for premiums for the first three months of 2014, then billed many for incorrect amounts afterward. The department also failed to terminate some recipients who failed to pay their premiums.

The audit concluded that the department needs better safeguards to ensure that data gets accurately and securely transferred from MNsure into the state’s medical payment system.

Medical Assistance, the state’s version of Medicaid, and Minnesota Care, which serves the working poor who don’t qualify for Medical Assistance, account for more than 315,000 of the nearly 371,000 signups through MNsure since the site launched in October 2013. The state paid $376 million in benefits for newly enrolled recipients in these programs through April.

The auditor’s office tested a random sample of 193 enrollees, finding that nearly 17 percent were ineligible for the programs in which they were enrolled, resulting in payment errors.

Human Services Commissioner Lucinda Jesson wrote in a formal response that her department continues to work on fixing the problems, which cropped up in late 2013 and early 2014 as a new eligibility system was rolled out under tight timelines.

“While problems are not unexpected on a new project, especially one of this scale and complexity, the scope of the problems we experienced is disappointing. …  While we made efforts to fix all identified problems, the priority was to ensure people did not wrongly lose coverage,” Jesson wrote.

The auditor’s office has raised concerns for more than 10 years about the DHS’ ability to ensure its eligibility determinations are correct, the report noted.

It cited several examples of incorrect determinations and payment errors. Some applicants were asked during the online sign-up process to verify income information that MNsure received from another state agency. In at least a few cases, MNsure mistakenly showed them an employer identification number rather than their income figure, resulting in some applicants being asked if their correct monthly income was $415,777,140, according to the audit. Most people caught the error but one mistakenly said it was correct, so she and her children were put in the wrong program.

The report recommended that the department do a better job of designing and testing its verification and error detection practices to ensure that they’re effective, and to try to recover overpayments.

The report marks the second of three reviews the auditor has been conducting related to MNsure, which is separate from the DHS.  A report last month looked at MNsure’s own internal controls. Another in February will be a broader evaluation of MNsure’s development and implementation.