I got I-485 approval notice from NSC center. It also say: "In processing your case we have reached the point where we need you to make an appointment to go to one of our application support center to have some additional biometrics taken. Call customer service at 1.8003755283 to schedule your appointment. We cann't complete certain steps in processing until you appear for this appointment. You must appear for your appointment within in 84 days from the data on this notice." But I already did the biometric last Oct, it is less than 1 year. Any body know what I should do? Thank you very much.