At first, I booked a sleeper bus from Hoang Long, but it was a new bus from A.BA. When I got on the sleeper bus, the staff collected the money and the bus driver enthusiastically advised me, so I paid an additional 350k to stay in a spacious room. Next time I change buses, the driver will pay in advance. Although it was a bit annoying, everyone on the bus was happy. I will see the new driver soon.