Kivymd can't add new list after the first button click

See more:

Python

Kivy

I have this button below that supposed to run a function called 'addList' which should add new list into the screen every times it was clicked, and it works on first click but then when I tried to press the button on second try the button won't work and isn't clickable.

self._addButton = MDRaisedButton(text="Upload File",
                                size_hint=(.4,.04),
                                pos_hint={'center_x':.2},
                                valign='bottom',
                                font_size="16sp",
                                md_bg_color="#121212",
                                on_release=self.addList)

What I have tried:

<pre>    def addList(self, _Obj):
        _sv = ScrollView()
        MainlistView = MDList()
        AddUser_item = TwoLineListItem(text="File 1",secondary_text="2/4/2022")
        MainlistView.add_widget(AddUser_item)
        _sv.add_widget(MainlistView)
        self.screen.add_widget(_sv)