One month before the expiration date , make an appointment with International Institut located at 670 Clinton Ave, Bridgeport and IMMIGRATION SERVICES will inform you every step of the way by mail.IDK gibe them
https://my.uscis.gov/exploremyoptions/renew_green_card
You can call the number to set an appointment. You'll need 540 for immigration and 120 for the appointment. Also a copy of your previous card. There is a chance the 540 can be waived and if you don't have a copy of your card then don't worry. All this and more can be answered if you set an appt up.
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