A data matching issue means the Marketplace is not able to verify the information on your application based on the data the Marketplace already has for you. To resolve the data matching issue with your application, the Marketplace is likely to contact you and ask you to verify your income. The Marketplace will provide you with 90 days to submit the required verification (and you will receive an automatic 60-day extension if you are unable to meet this deadline). You can also do so by uploading documents to the Marketplace online or by sending photocopies in the mail. Verifying documents can include a federal or state tax return, a letter of termination, or pay stubs. To determine which documents you need to submit, please consult this guide here. You can request an extension by calling the Marketplace call center (1-800-318-2596, or TTY: 1-855-889-4325 for HealthCare.gov).