inconsitencies in my first code

[metulburr]

You need to dedent this section back into the while loop instead of the event loop

    if y1 >= 490:
        yvel *= -1

to like this

while True:
 
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
 
    if y1 >= 490:
        yvel *= -1