The issue is that the mobile menu keeps disappearing. It is a flyout menu and it pops out on mobile, but the actual navigation links aren't there. When I go to theme.liquid file and revert back to previous version, it works.
I installed an app for megamenu that replaced the theme nav and it worked for a few hours, but then it also reverted to the blank menu.
I do not know if it is an app or what and I have spent the last 2 days trying to figure this out.