[FONT=Arial, Helvetica, sans-serif]Don't worry about having to obtain a letter since you weren't required to apply. You'll be able to show [/FONT][FONT=Arial, Helvetica, sans-serif][FONT=Arial, Helvetica, sans-serif]this at interview by your inital entry date into US (USCIS also has this info on file).
You can always call SSI at [/FONT][/FONT][FONT=Arial, Helvetica, sans-serif][FONT=Arial, Helvetica, sans-serif]847-688-6888 if you rather get a letter of no SSI registration.
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