Why does my character only move left when I use pygame.key.get_pressed()?

Question

I'm new to Python but I decided to give it a try making a fighting game in Pygame. My character will only move left and only when an update is forced.

I tried:

KEY DOWN

if event.key == pygame.K_d:

KEY UP

if event.key == pygame.K_d or event.key == pygame.K_a:
    x_change = 0

And it works to an extent. It's just annoying when you need to suddenly change direction, but can't change direction.

I also changed the OR with AND, so it will stop when both are lifted, but that prevents movement from both directions.

Made it do so I can move while not fighting for testing reasons

fighting = False

while not fighting:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            fighting - False

        keys = pygame.key.get_pressed()

        if keys[pygame.K_a]:
            x_change1 = -5

        if keys[pygame.K_d]:
            x_change1 = 5

        if not keys[pygame.K_a] and keys[pygame.K_d]:
            x_change1 = 0 

        x1 += x_change1


    gameDisplay.fill(white)
    fighter1(x1,y1)
    pygame.display.update()
    clock.tick(28)

My guy moves X pixels left only when I force an update such as pressing A again (left) lifting A or moving my mouse over the window. D (right) registers but doesn't move. Once A is pressed, it won't stop going even if the key is up.
I want to fix this so I can then more easily add jumping, attacks and a player 2.

Answer 1

You are missing a not operator here:

if not keys[pygame.K_a] and keys[pygame.K_d]:
    x_change1 = 0 

Add it like this:

if not keys[pygame.K_a] and not keys[pygame.K_d]:
    x_change1 = 0