Problem with drop down menu

Hello!

I noticed a problem with the behavior of the main menu on mobile devices when I’m using Voluto theme.

When more than one sub-menu appears on the main menu, no matter which drop-down is clicked. Only the first submenu (expandable element) always develops.

This makes it impossible to have several sub-menus on the page. I don’t know how to fix this, and the size of the menu without drop-down lists keeps growing.

Help please!
Site with problem – video

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