It’s worth trying to call them. My application remained pending approval for more than a week until I finally called the embassy. The same day they approved. It was another consulate though, not Vietnam
As they initially put Vietnam in a country field there, apparently you put your hotel address in Vietnam. Below you choose no and put your US address. I was also confused in address and location sections while completing, haven’t submitted yet though
I remember reading some cases from this group they paid only after they were told they are likely to be approved. It may only work for walk in applications though