Sorry for my late reply. I went to bed last night after I sent myposter.
I haven't got my GC yet. After interview in local office I was told my NC still pending.
The message I sent yesterday is the email from my laywer, he told me a case he attended the interview with his client, that is not my case. Sorry for confusing you.
You are right, I lived in Baltimore, MD, not DC. So I don't know where my lawyer attended the interview with his client in DC.