Getting KeyError while using this

[Prince2347X]

Hey, this is my code:

import os


from kivymd.app import MDApp
from kaki.app import App
from kivy.factory import Factory




# main app class for kaki app with kivymd modules
class LiveApp(MDApp, App):
    """ Hi Windows users """

    DEBUG = 1 # set this to 0 make live app not working

    # *.kv files to watch
    KV_FILES = {
        os.path.join(os.getcwd(), "login_screen.kv"),
    }

    # class to watch from *.py files
    CLASSES = {
        "Airlines": "main",
        "LoginScreen": "login_screen",
    }

    # auto reload path
    AUTORELOADER_PATHS = [
        (".", {"recursive": True}),
    ]


    def build_app(self):
        return Factory.Airlines()




# finally, run the app
if __name__ == "__main__":
    LiveApp().run()

and i'm getting this error and being stuck at the white screen...

here is the file structure..:

@prsfx Help!