Yes. You must request any extension before the 90-day deadline runs out. You can request the extension in writing or through the marketplace call center. In your request you should include your name, a description of the supporting documents requested, the reason you need an extension, and the amount of additional time you need. You may want to ask a Navigator for help requesting an extension. (45 C.F.R. §§ 155.315 and 155.320).