Hi Chika, the NVC contact us through email. We listed our email addresses at the first stage, but I believe you can add it on the CEAC website as well.
I have not o.still at the nvc.we submitted our documents. My husband is the one keeping us for now.he didn't like his 2019 tax returns so he is doing it now and its also wasting time too.but its well .hope you are good.