(I know you said you've been here a while, but for others - at least in Texas if it's different elsewhere - have to wait 10 days after arrival to apply - can apply on the 10th day.)
To prove your U.S. immigration status, you must show us the current U.S. immigration document, I-94, Arrival/Departure Record, issued to you when you arrived in the United States.
If you are an F-1 or M-1 student, you also must show us your I-20, Certificate of Eligibility for Non-immigrant Student Status. If you are a J-1 or J-2 exchange visitor, you must show us your DS-2019, Certificate of Eligibility for Exchange Visitor Status.
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