Menu not Working On Mobile Devices

I’ve tested on both my live and staging sites both running WordPress v5.5.1 and have disabled any plugins on my staging site to ensure they are not causing any issues.

The main site menu works fine on desktop/laptops, however, when users visit the website on a mobile device the site menu doesn’t appear to work.

Please could this be looked into?

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