[Error] application closes when pressing checkbuttom

Hello, I have a problem that I do not understand.

Everything works fine but sometimes the application crashes and closes (tkinter window) when clicking on the checkbuttom

What should it be?
It does not throw any code error or anything, it just closes the application without further ado and I get this in the editor:

self.check_Tarjeta = IntVar()
		self.b_Tarjeta = Checkbutton(self.pagina1, text="TARJETA",font="Helvetica 15 bold", variable=self.check_Tarjeta)
		self.b_Tarjeta.place(x=650, y=400, width=200, height=30)

		### CHECK EFECTIVO ###
		self.check_Efectivo = IntVar()
		self.b_Efectivo = Checkbutton(self.pagina1, text="EFECTIVO",font="Helvetica 15 bold", variable=self.check_Efectivo)
		self.b_Efectivo.place(x=650, y=440, width=200, height=30)

if self.check_Tarjeta.get() == 1 and self.check_Efectivo.get() ==1:
			MessageBox.showinfo("ERROR", "One 1", icon="error")
		elif self.check_Tarjeta.get() == 1:
			MessageBox.showinfo("ERROR", "TARJETA", icon="error")
		elif self.check_Efectivo.get() == 1:
			MessageBox.showinfo("ERROR", "EFECTIVO", icon="error")
		else:
			MessageBox.showinfo("ERROR", "Select", icon="error")

[Finished in 7.7s with exit code -5]
[cmd: ['python3', '-u', '/Users/tomas/Downloads/PROYECTO/main.py']]
[dir: /Users/tomas/Downloads/PROYECTO]
[path: /Library/Frameworks/Python.framework/Versions/3.10/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Library/Apple/usr/bin]

What can cause this error that closes the application without further ado?