Trying to add an image that functions like a butto

I already have a set of code that is similarly formatted as the one below, and that seems to work. But somehow, the image for this one isn't popping up. And they're in the same folder as the code. Def small is the code that has the image working, and def stripes is the one that is giving me an error.

from tkinter import *
import tkinter as tk
from tkinter import ttk

def small():
    s = Tk()
    s.title('Small Preset Shirt (Not fit to scale)')
    canvas = Canvas(s, width = 800, height = 100)
    canvas.pack()
    b1=ttk.Button(s,text='Click to Start', command = questions)
    b1.pack()
    photo = PhotoImage(file = 'small.png')
    b1.config(image=photo,compound=RIGHT)
    s.mainloop()

def stripes():
    stripes = Tk()
    stripes.title('Black Shirt with Stripes')
    canvas = Canvas(stripes, width = 800, height = 100)
    canvas.pack()
    b2=ttk.Button(stripes,text='Click to See Final Price', command = final)
    b2.pack()
    photo = PhotoImage(file = 'stripes.png')
    b2.config(image=photo,compound=RIGHT)
    stripes.mainloop()

Here is the full Traceback:

Exception in Tkinter callback
Traceback (most recent call last):
File              "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/tkinter        /__init__.py", line 1705, in __call__
return self.func(*args)
File "/Users/Business/Documents/Python/small.py", line 159, in  stripes
b2.config(image=photo,compound=RIGHT)
File  "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/tkinter.   /__init__.py", line 1485, in configure
return self._configure('configure', cnf, kw)
File   "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/tkinter.   /__init__.py", line 1476, in _configure
self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
_tkinter.TclError: image "pyimage2" doesn't exist

When you get an error message "_tkinter.TclError: image "pyimage2" doesn't exist" or something like that then it means tkinter can't decide which window's photo it is. This is due to of more than one Tk() windows. There are few other things that create problems when you use more than one Tk, that is why Tkinter have another type of window Toplevel and it refers to the main window like a child window.

Lets get to your code..

Here I see few other problems other than just that error.

Like I said not more than one Tk() window. I believe you probably have more than two.
If you have a main window and decide to open few more with Toplevel then please don't use another mainloop() one is sufficient to open as many Toplevel windows but remember to use at least one mainloop() at the end of your code.
Sometimes when you define a Photoimage in a function which stored an image in a local variable the image is cleared by python even if it’s being displayed by the Label or Canvas. So always create a reference in that case.

As your code is not runnable so I added necessary things to run and test it.

from tkinter import *
from tkinter import ttk

Main_window = Tk()  # Make only one Tk main window 
Main_window.geometry('300x150')
Main_window.title("Get Shirts (Buy 1 get 1 Free)")

def small():
    s = Toplevel()   # For secondary window use Toplevel 
    s.title('Small Preset Shirt (Not fit to scale)')
    canvas = Canvas(s, width = 800, height = 100)
    canvas.pack()
    b1=ttk.Button(s,text='Click to Start', command = None)
    b1.pack()
    photo = PhotoImage(file = 'logo.png')
    b1.img_ref = photo      # Create a reference 
    b1.config(image=photo,compound=RIGHT)
    # s.mainloop()      # Don't use mainloop more than once


def stripes():
    stripes = Toplevel()  # For secondary window use Toplevel 
    stripes.title('Black Shirt with Stripes')
    canvas = Canvas(stripes, width = 800, height = 100)
    canvas.pack()
    b2=ttk.Button(stripes,text='Click to See Final Price', command = None)
    b2.pack()
    photo = PhotoImage(file = 'logo.png')
    b2.img_ref = photo      # Sometimes images in functions becomes garbage value.
    b2.config(image=photo,compound=RIGHT)
    # stripes.mainloop()      # Using two of these will do nothnig.


Category_Lb = Label(Main_window, text='Category', font=('',25))
Category_Lb.pack()

Cate_1 = ttk.Button(Main_window, text='Small Preset Shirt', command=small)
Cate_1.pack()

Cate_2 = ttk.Button(Main_window, text='Black Shirt with Stripes', command=stripes)
Cate_2.pack()


Main_window.mainloop()