Beaver Builder custom header incorrectly displaying menu as vertical and wrong font

I’m having this VERY inconsistent issue with my main navigation.

I created a customer header for the site by creating a “page” with the header design.

Sometimes it renders correctly. Sometimes it displays the wrong fonts (serif) and is vertical instead of a centered horizontal menu, as designed.

I don’t get where the problem is coming from and why it’s inconsistent. Help?

The only thing that’s correctly styled in that image is the logo.