menu not working in mobile view

I have created a ConverioVersion: 1.0.10 theme and got a website running: https://supreme-app.com/ The menu works fine except on mobile devices (Iphone4 and Android). The menu button appears but nothing happens when I click it. I have looked at other posts and tried deactivating Plugins but this does not help. I am not a developer and am very new to WP. Any help would be greatly appreciated.