Responsive Menu Not Fixed

I’m just starting to set up my site and I really want to get the functionality dialed before I spend time on any additional pages. I followed some other threads to fix the menu bar to the top of the screen so that it scrolls down with the user. It works great!

My problem now is that the responsive hamburger menu will not follow the menu bar down the screen. If you scroll down in responsive mode, the hamburger icon follows you, but once you click it the page options remain at the top of the page and you have to scroll up to see them. Additionally once you scroll up, half of the options are hidden behind the header.

How can I get the hamburger menu to work as the desktop menu works? Please advise.

This is probably much easier to just view on my page.

Thanks so much for any help!

Any help please? Really need to get this sorted out before moving forward.