Americans covered by health insurance through the federal exchange have until Friday to provide missing information or they will lose coverage Sept. 30. As part of the ongoing rollout of the Affordable Care Act, the Federal Health Insurance Marketplace sent notices Aug. 12 to some 310,000 policyholders nationwide with a citizenship or immigration data-matching issue who have not responded to previous notices via mail, email and phone. Some 21,000 of those were from Georgia, which has more residents facing the deadline than any of its neighboring states, except Florida, with 93,800.