Sorry for the late response. I emailed the US embassy multiple times. They finally replied that they will email the instructions to register to my fiancé. They emailed her later that day with the instructions. We scheduled our interview and finally got our visa. Keep contacting the US embassy until they send you the instructions. One thing we learned in this journey is that instead of waiting like they are telling you, you should keep contacting them (USCIS, NVC, US Embassy, etc.) until they do their jobs.
