More than 300,000 Obamacare enrollees have yet to provide information on their legal residency or citizenship, according to the government. Those individuals have until September 5 to send complete information to the government before losing coverage on September 30. 

Where residency information is still needed. (Note: the data
only includes federal exchange states.) Via HHS

According the data provided by the government, in May 970,000 people had citizenship data errors in their Obamacare applications. As of August, 450,000 of those cases have been resolved, 210,000 are in progress and 60,000 new documents arrive every day. The 310,000 remaining applicants will receive two more phone calls and one more email. 

In June the Associated Press reported that 2 million enrollees were missing information on immigration, citizenship and income that could jeopardize their subsidies and insurance plans. At the time the Department of Health and Human Services expected that most the of inconsistencies would be cleared up by the end of the summer.

Critics of the health care law have noted that the government doesn't have a system in place to verify information it receives from consumers. Last month the Government Accountability Office was able to gain subsidized health insurance for 11 out of 18 fake accounts. The government has argued that a data inconsistency doesn't mean there's a problem with the application. As The New York Times noted earlier this summer, consumers often run into problems uploading files to Healthcare.gov, or are asked to send in files they've already sent.