Nice job.
The level transition is good. It's just a shame when I accidently trigger it by walking off screen. Maybe you could lock the player in each map until they deliver all the packages to fix that? On the bright side, I'm glad I don't have to backtrack all the way to the truck after ever package. That would have made some of the later sections frustrating. But since the game was pretty forgiving, it was pretty chill.
The game as a whole has a nice set of personality. The dialogue you get delivering everything in an area, the music (outside of a maybe a slight improvement to the looping), and of course, that flipping truck.
Keep up the good work.