The federal government could be giving more subsidies to Americans who signed up for health care under ObamaCare than they deserve, a new report from the Washington Post says.

The government has found errors that show income differences between what people put on their health care applications and what they put on their tax forms. They've found the errors, but haven't been able to fix them, the report says.

Income information is used to determine how much in government subsidies an individual gets for health care. They may be getting too much in subsidies, or even too little.

Federal health officials have tried to request income verification from those they identified with having an income discrepancy, but few have returned their requests by sending in pay stubs or other proof of income.

The Washington Post was able to obtain internal documents that show these income discrepancies appear on 1.1 million to 1.5 million applications.

There's no method to match income proof with the applications that contained errors. That means, starting this summer, officials will have to manually review the income and subsidy levels of all the applications that contained errors.

If found receiving excess subsidies, Americans will have to return any unwarranted payments next year, the report says.

"While most data matched up right away during the application process, we take seriously the cases that require more work and have a system in place to expeditiously resolve these data inconsistencies," Julie Bataille, communications director for the Centers of Medicare and Medicaid Services, told The Post.

Bataille added that federal officials continue to work hard to make sure everyone is receiving the proper amount of tax credits and no one is receiving too many tax credits.

Still, some are worried that these errors on applications could lead to disasters for individual Americans.

"I have this sick feeling that there are these people out there who have made unintentional errors, and in a few years will be subject to massive tax bills," Jessica Waltman, senior vice president for government affairs at the National Association of Health Underwriters, told The Post.