Sticky/ scroll Navbar on Template not working

Hello
I recently got this template:

I’m having trouble editing the nav bar that comes down when scrolling. I already finished the version of the nav bar at the very top, but when I select the instance that is on the scroll, it shows above the page almost out of site and seems to have the correct info, but doesn’t show correctly when I preview the site.

Does anyone have a way to fix this?

Thank you!!