Adjustment of Status - I-485

I did my GC interview this Monday 7/18. My husband and I was doing long distance relationship for two and a half years since we are both graduate students. We prepared a lot to prove that we maintained a good relationship. But the office just basically checked the info on the application and wasn't interested in our story or relationship. She didn't ask for any photos, but she was struggling with my husband's citizenship.

My husband came to US when he was 8 and got citizenship through parents at age of 14. He doesn't have a naturalization certificate because it wasn't required. So apparently the officer said the US passport is not enough to prove his citizenship and asked for naturalization certificate or his parents' passport copies and naturalization (?????) Our lawyer was there ,so she spoke for us and said it was the first time that was asked. The officer said she needs to review his citizenship and didn't say anything about my case.

It has been 4 days but the case status was still " your interview was scheduled on...." Does anyone have a similar situation? Any idea or advice? Thank you!