Rescheduling a Biometrics Appointment
Many types of immigration applications require the person (if living in the United States) to attend a biometrics appointment at an Application Service Center. There, fingerprints and other information are collected. Your biometrics appointment notice will arrive on USCIS Form I-797C.
Near the bottom of that notice, you’ll see a box you can check saying “Please reschedule my appointment.” You’ll need to check the box, make a copy of the notice for your records, and send the original back to USCIS at the address indicated.