Un-Responsive Menu

Hello All!

I inherited work on a WordPress site and have been making adjustments and adding things to it but the original designer built the template from scratch (working on customer to change and update look but that’s a different problem).

He used something called twig and a number of external files which I am learning how they tie into the site. But the problem is in mobile view, the menu button doesn’t do anything, just loops back to initial page and I am at a loss as to how to get it to work properly.

I tried a plugin, thinking to bypass the original code all together but those don’t seem to work either which is vexing.

If anyone could take a look and make some suggestions for me, I’d appreciate it.