Submenu behaving weirdly

Hi, I have two sites, both running enfold, and themed also exactly the same way.
However, the submenu on one of my site is not functioning properly. It’s not sticky, it’s not loading properly in mobile view.
I’ve checked through all my settings for both sites, tried to do a fresh install of wordpress and the theme, but is unable to find the problem.

The websites in question are afa.org.sg and gayhealth.sg