Responsive Menu and Responsive Dropdown Menu

The above two menus work fine on Desktop version of the website but on mobile version, the "about" tab when clicked, it opens the 'community' and 'testimonial' dropdown and 'about' page doesn't open.
Similarly, when "projects" tab is clicked, the 'c' dropdown shows and "projects" page doesn't open and again when 'c' tab is clicked to open, the dropdown 'b' and 'c' opens hence the main 'c' page doesn't open.
I know its quite confusing...
Please watch a live demo here. https://lucknowwebs.com/responsive-menu/home.html
Please suggest a better Menu to take care of this problem as the clients structure can not change.