I posted earlier about our experience of my partner's application being rejected in Hanoi despite having all the correct paperwork, which we had compiled ourselves. We're starting to think it was because an agent submitted it on our behalf, using an agency email address which is clearly not a personal one. There have been cases of agents submitting non genuine paperwork for clients. It's speculation still but it seems like one of the most plausible reasons for the rejection.

The agent we used wasn't expensive. Total price including embassy fee was 16k but it wasn't worth it for us. He is reapplying soon, maybe tomorrow or the next day but has been in Hanoi since 15th. It was a costly mistake for us.