Menu with submenus, use of MainLoop

When I am using menus and open two submenus - windows, when I am using MainLoop for each page, receive error -

Process finished with exit code -1073740791 (0xC0000409)

When I am not using MainLoop, I can not close the subwindows. I know that the library must be better but...

from tkinter import *
from tkinter.filedialog import askopenfilename
import tkinter as tk
from tkinter import ttk
import mysql.connector
from artikuli import artikuli
from dokumenti import dokumenti
from dokumenti1 import dokumenti1
from hronologia import hronologia
from oborved import oborotnaved
from oborved1 import oborotnaved1
....
root = Tk ( )
menu = Menu ( root )
root.config ( menu = menu )
root.geometry ( '400x300' )
nomenklaturi = Menu ( menu )
menu.add_cascade ( label = "Номенклатури" , menu = nomenklaturi )
nomenklaturi.add_command ( label = "Контрагенти" , command = contragents )
nomenklaturi.add_command ( label = "Стоки и услуги" , command = artikuli )
#filemenu.add_command ( label = "Open..." , command = OpenFile )
nomenklaturi.add_separator ( )
nomenklaturi.add_command ( label = "Exit" , command = root.quit )
vavejdane = Menu ( menu )
menu.add_cascade ( label = "Въвеждане" , menu = vavejdane )
#vavejdane.add_command ( label = "Документи" , command = dokumenti )
vavejdane.add_command ( label = "Документи1" , command = dokumenti1 )
#helpmenu.add_command ( label = "About..." , command = About )
spravki = Menu ( menu )
menu.add_cascade ( label = "Справки" , menu = spravki )
spravki.add_command ( label = "По хронология" , command = hronologia )
spravki.add_command ( label = "Оборотна ведомост" , command = oborotnaved )
#spravki.add_command ( label = "Оборотна ведомост1" , command = oborotnaved1         
)
root.mainloop ( )

and the other windows -

1
from tkinter import *
from tkinter.filedialog import askopenfilename
import tkinter as tk
from tkinter import ttk
import mysql.connector
from artikuli import artikuli
import datetime
import wx
import wx.grid
import tkinter.messagebox
from openpyxl import Workbook
from openpyxl.chart import BarChart, Reference
from functools import partial
from datetime import date
from datetime import time
from datetime import datetime
import datetime
...
app = wx.App()
frame = MyFrame()
frame.Show()
app.MainLoop()

2
from tkinter import *
from tkinter.filedialog import askopenfilename
import tkinter as tk
from tkinter import ttk
import mysql.connector
import datetime
import wx
import wx.grid
import tkinter.messagebox
from openpyxl import Workbook
from openpyxl.chart import BarChart, Reference
from functools import partial
from wx.lib.scrolledpanel import ScrolledPanel
import wx.grid as gridlib
...
app2 = wx.App (False )
frame2 = oborotka ( )
frame2.Show ( )
app2.MainLoop ( )