If you are a permanent resident of the US with a Form I-551 that is effective for ten years and your green card is expired or will expire in the coming six months, it is time you should renew your green card. You can initiate the green card renewal process by filing Form I-90 online or on a paper. The Form I-90 is an Application to Replace Permanent Resident Card.
If you are outside the US and your green card is expiring within the next six months, you must renew your green card as soon as you arrive in the US if you are returning to the US within one year of your exit from the US.
Furthermore, if the green card holder is outside the US at the time of expiry of the card and he/she has not filed an application for renewal of the card, he/she should consult with the US Consulate, US port of entry, or the USCIS office in the foreign country prior to applying for renewal of the green card.
In case, your application for renewing your green card is rejected, the USCIS will send you a notification about it. The letter will also cite the reasons for denial of your application; however, you are not allowed to appeal the denial. Instead, the applicant has the choice to file a motion to reinitiate or a motion to review with the office that denied the application for renewal of the green card. By doing so, you actually ask the USCIS to reconsider or reevaluate its decision.
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