US Immigration from Hong Kong

My fianc had an interview they told her she needed to update her D160 they did not give her any instruction on how to anyone experience this what do you do

As our NOA-2 gets closer, anxiety begins to set in as we question our process to make sure we've done everything correctly. Just looking for a bit of validation, as we're 95% sure we're fine.
My fianc e is a Chinese citizen, currently living and working in Hong Kong. She has a renewable work visa that allows employment and legal residency in HK. Based on this, we submitted Hong Kong as the desired embassy for her K1-Visa and interview process.

From my understanding, there shouldn't be any issues with this as long as we secure the police report from both Hong Kong and China, right?

So me (from Hong Kong, a permanent resident in usa) and my husband (us citizen) have a child (he s 29 months old now)

id like to ask obviously he is a USA citizen, but is he a Hong Kong citizen as well since I am a Hong Kong citizen? And if so, what I need to do or where I should contact to get a Hong Kong passport or ID for our son? Do we need to back to Hong Kong for this?

So I had n400 interview in May and I got denied because they said that I was out of the country a lot.

Then my family helped me filed n336 to request a hearing in June.

I got a confirmation mail and never heard back again. I saw some people say they were asked to do fingerprint but i never received any appointment mail.

Does anyone know how long it takes to progress

Thankyou so much

Where can I go to change the address for my beneficiary before time comes for the interview process? She recently moved to a different location in Hong Kong.

Checking on the USCIS website, I can only find options to change my address if I move as the petitioner.