Generate mobile menu toggle override not working

I’m building a website in generate press but I’ve run into an issue with the hamburger menu on screens under 1005px. It doesn’t switch to a hamburger menu, it is a very buggy-looking desktop menu.

There is a support request with similar issue at

https://www.ads-software.com/support/topic/bug-with-the-hamburger-menu/

The guy in this request gave the following screenshots, which are exactly what I experience.

On iPad: https://i.imgur.com/PUnVTsL.png
On desktop (wordpress preview: tablet): https://i.imgur.com/xVBl1OR.png

I tried to apply proposed solution to use snippet as described at

https://docs.generatepress.com/article/generate_mobile_menu_media_query/

add_filter( 'generate_mobile_menu_media_query', function() {
    return '(max-width: 1024px)';
} );

add_filter( 'generate_not_mobile_menu_media_query', function() {     
	return '(min-width: 1001px)';
} );

however when I input the PHP snippet into my child theme functions.php file and flush cache, nothing happens.

Can someone point me into right direction, either how to change the code or where to input the code?

Thank you.

Lubo

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