The cursors in my clicker game keep multiplying

Question

So I am making an idle clicker game (which in no shape, way, or form is related to snake), and I wanted to add a cursor that when clicked, would add +1 points every second. Here is the code for how the cursor increases points:

def display_score():
    global points
    present = (int(pygame.time.get_ticks() / 1000) - int(start_time / 1000)) * (cursors * 1)
    points += present
    #print(present)
    score = font.render(f"{points}", False, (0, 0, 0))
    score_rct = score.get_rect(center = (320, 60))
    screen.blit(score, score_rct)

Then I tried making it so that it costs 10 points to buy a cursor. Here is what I wrote:

        if event.type == pygame.MOUSEBUTTONDOWN:
            if cursor_rct.collidepoint(event.pos) and points >= 10:
                    points -= 10
                    cursors += 1

Instead of buying 1 cursor and then stopping, the game kept buying more cursors for no apparent reason.

Full code:

import pygame
pygame.init()

screen = pygame.display.set_mode((640, 640))
clock = pygame.time.Clock()
mouse_pos = pygame.mouse.get_pos()
points = 0
cursors = 0
start_time = pygame.time.get_ticks()
font = pygame.font.Font("PixelType.ttf", 75)

#text = font.render("h", False, (0, 0, 0))
#text_rct = text.get_rect(center = (320, 60))

def display_score():
    global points
    present = (int(pygame.time.get_ticks() / 1000) - int(start_time / 1000)) * (cursors * 1)
    points += present
    #print(present)
    score = font.render(f"{points}", False, (0, 0, 0))
    score_rct = score.get_rect(center = (320, 60))
    screen.blit(score, score_rct)


backround = pygame.image.load("graphics/backround.png").convert_alpha()
backround_rct = backround.get_rect(topleft = (0, 0))

cookie = pygame.image.load("graphics/cockie.png").convert_alpha()
cookie_rct = cookie.get_rect(center = (320, 320))

cursor = pygame.image.load("graphics/cursor.png").convert_alpha()
cursor_rct = cursor.get_rect(center = (320, 580))


run = True
while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False
        if event.type == pygame.MOUSEBUTTONDOWN:
            if cookie_rct.collidepoint(event.pos):
                points += 1
            if cursor_rct.collidepoint(event.pos) and points >= 10:
                    points -= 10
                    cursors += 1
                    
            
    screen.blit(backround, backround_rct)
    screen.blit(cookie, cookie_rct)
    screen.blit(cursor,cursor_rct)
    display_score()

    


    pygame.display.update()
    clock.tick(60)