If they don’t like the look of you, they don’t like the look of you!  Happened to a cousin of mine Oxford educated has a big Afro haircut and the Chinese were like nope! Turned him around.
Yeah well said I could have saved changing my flight and staying in Vietnam longer had I done this. I just followed what they asked me on the initial form 😂
They didn’t do anything wrong where’s the questionable history? Why would you be denied when your visa is approved, the officer would have looked at the history and granted the visa. Seems strange but ok. No one else seems to have had a problem once granted.