Visibility Attribute in PySimpleGUI makes button stop working

Question

How do I fix this?

layout = [
    [sg.Text("Welcome to blackjack!")],
    [sg.Text(F"Your cards: {player_cards}", key='pc')],
    [sg.Text(F"The value of your cards: {player_value}", key='pv')],
    [sg.Text(F"Dealer cards: [{computer_cards[0]}, ---]", key="cc")],
    [sg.Text("", key="cv")],
    [sg.Text("", key="results")],
    [sg.Button("Deal", key='-BUT1-'), sg.Button("Stand", key='-BUT2-')],
]

window = sg.Window("the box", layout)

while True:

    event, values = window.read()
    check_win()

    if event == sg.WIN_CLOSED:
        break
    elif event == "Deal":
        deal()
        window['pc'].update(F"Your cards: {player_cards}")
        window['pv'].update(F"The value of your cards: {player_value}")
        check_win()
    elif event == "Stand":
        end_game()
        window['-BUT1-'].update(visible=False)
        window['-BUT2-'].update(visible=False)


window.close()

Adding the .update() code near the end to -BUT1- and -BUT2- makes the buttons stop working entirely. I don't understand why this is happening. How do I fix this? Also note any functions being called were removed because stackoverflow wouldn't let me post otherwise.