Homepage Menu don’t show

Hello,
I have installed the Polylang plugin on this page (https://wein-werte.com/). After I activated the plugin, the menu on the homepage disappeared. When I deactivate the plugin, the menu is visible again normally. I also deactivated all plugins except the Polylang plugin and the menu was also gone. Do you have any idea what the problem could be?

The page I need help with: [log in to see the link]