Bug in Toolbar about spigui HOT 4 OPEN

private void openJoinInventory(Player player){
    SGMenu menu = getMessageMenu("§aJoin Messages", player, CustomMessageType.JOIN);
    player.playSound(player.getLocation(), Sound.ENTITY_CHICKEN_EGG, 1, 1);
    player.openInventory(menu.getInventory());
}

private SGMenu getMessageMenu(String title, Player player){
    List<String> messages = new ArrayList<>();
    for(int i = 0; i<50; i++){
            messages.add("String " + i);
    }
    SGMenu menu = this.gui.create(title, 6);
    menu.setAutomaticPaginationEnabled(true);
    menu.setRowsPerPage(5);
    for(String msg : messages){
        ItemStack msgStack = new ItemBuilder(Material.PAPER).name(msg).build();
        SGButton messageButton = new SGButton(msgStack).withListener(event -> {
            Player clicker = (Player) event.getWhoClicked();
            clicker.playSound(clicker.getLocation(), Sound.ENTITY_PLAYER_LEVELUP, 1, 1);
        });
        menu.addButton(messageButton);
    }
    setupToolBar(menu, CustomMessageType.JOIN);
    return menu;
}

private void setupToolBar(SGMenu menu){
    menu.setToolbarBuilder((slot, page, buttonType, sgMenu) -> switch (buttonType) {
        case CURRENT_BUTTON -> new SGButton(new ItemBuilder(Material.NAME_TAG)
                .name("&7&lSeite " + (menu.getCurrentPage() + 1) + " von " + menu.getMaxPage())
                .build()
        ).withListener(event -> event.setResult(Event.Result.DENY));

        case NEXT_BUTTON -> {
            if (page == menu.getMaxPage()) yield null;

            if (menu.getCurrentPage() < menu.getMaxPage() - 1) {
                yield new SGButton(new ItemBuilder(NEXT_SKULL)
                        .name("&a&lNächste Seite →")
                        .build()
                ).withListener(event -> {
                    event.setResult(Event.Result.DENY);
                    menu.nextPage(event.getWhoClicked());
                    Player player = (Player) event.getWhoClicked();
                    player.playSound(player.getLocation(), Sound.ITEM_BOOK_PAGE_TURN, 1, 1);
                });
            }
            yield null;
        }

        case PREV_BUTTON -> {
            if (page == 0) yield null;

            if (menu.getCurrentPage() > 0) {
                yield new SGButton(new ItemBuilder(BACK_SKULL)
                        .name("&a&l← Vorherige Seite").build()
                    ).withListener(event -> {
                        event.setResult(Event.Result.DENY);
                        menu.previousPage(event.getWhoClicked());
                        Player player = (Player) event.getWhoClicked();
                        player.playSound(player.getLocation(), Sound.ITEM_BOOK_PAGE_TURN, 1, 1);
                    });
            }
            yield null;

        }

        case UNASSIGNED -> {
            if(slot == 1) {
                yield new SGButton(HOME_SKULL)
                        .withListener(event -> {
                            Player player = (Player) event.getWhoClicked();
				player.closeInventory();
                            player.playSound(player.getLocation(), Sound.ENTITY_EXPERIENCE_ORB_PICKUP, 1, 1);
                        });
            } else if(slot == 7) {
                yield new SGButton(
                        new ItemBuilder(Material.LAVA_BUCKET).name("§cClear Message").build()
                ).withListener(event -> {
                    Player player = (Player) event.getWhoClicked();
		player.closeInventory();
                    player.playSound(player.getLocation(), Sound.ENTITY_GENERIC_BURN, 1, 1);
                });
            }
            yield null;
        }
    });
}