Why are my composite PNGs black when using pillow?

Question

For a final in one of my classes we basically had to make an NFT generator using pillow. I am a beginner with coding and so I googled some things and put together a code that would take random selections from PNGs I had made on photoshop and paste them on top of each other in random combinations. From what I can tell everything works fine, but the final image doesn't show any color, just black for filled areas and white for transparent ones. Its a very simple code so I will post most of it so you can see what I am talking about. Obviously y'all won't have all of my image files so I included only one of the dictionaries that reference them just so you know how I did it.

dict4 = {
    "0": "C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/blue.png",
    "1": "C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/green.png",
    "2":"C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/orange.png",
    "3":"C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/pink.png",
    "4":"C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/purple.png",
    "5":"C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/red.png",
    "6":"C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/teal.png",
    "7":"C:/Users/allib/OneDrive/Documents/SCHOOL CLASS FOLDERS/Vist 270/Final/worm_color/yellow.png",

}

# List section where the random selection will come from
worm_eye_lst = [dict['0'],dict['1'],dict['2'],dict['3'],dict['4'],dict['5'],dict['6'],dict['7'],dict['8'],dict['9']]

worm_hat_lst = [dict2['0'],dict2['1'],dict2['2'],dict2['3'],dict2['4']]

worm_eyebrow_list = [dict3['0'],dict3['1'],dict3['2'],dict3['3'],dict3['4']]

worm_color_list = [dict4['0'],dict4['1'],dict4['2'],dict4['3'],dict4['4'],dict4['5'],dict4['6'],dict4['7']]




# Random selection function
def rand_attr(lst):
    number_bank=len(lst)-1
    choice = random.randint(0,number_bank)
    return choice


# Function that puts all the pictures together
def composite_pic():
    bg = Image.open("background.png")
    cc=rand_attr(worm_color_list)
    print(cc)
    color_choice = worm_color_list[cc]
    color = Image.open(color_choice)
    bg.paste(color, (0, 0), mask = color)
    base_worm = Image.open("base_worm.png")
    bg.paste(base_worm, (0,0), mask = base_worm)
    ec=rand_attr(worm_eye_lst)
    print(ec)
    eye_choice = worm_eye_lst[ec]
    eye = Image.open(eye_choice)
    bg.paste(eye, (0, 0), mask = eye)
    hc = rand_attr(worm_hat_lst)
    print(hc)
    hat_choice= worm_hat_lst[hc]
    hat = Image.open(hat_choice)
    bg.paste(hat, (0, 0), mask = hat)
    ebc = rand_attr(worm_eyebrow_list)
    print(ebc)
    eyebrow_choice = worm_eyebrow_list[ebc]
    eyebrow = Image.open(eyebrow_choice)
    bg.paste(eyebrow, (0,0), mask = eyebrow)
    bg.show()


composite_pic()

Picture of the wrong output