I missed the deadline for submitting additional documentation to the marketplace to prove my eligibility (to buy coverage or to qualify for premium tax credits or to receive an exemption). Can I request an extension?

If the marketplace hasn’t received the requested information within 90 days and you didn’t already ask for an extension, the marketplace will make a determination based on the information it has. If you disagree with that decision you can appeal. (45 C.F.R. § 155.355; 45 C.F.R. § 155.505).