Top menu disappears after scrolling back up (after modifying header)

Hi. I want to have a different header for all pages except the home page… I actually don’t like the way this theme sets the image for the header, and would prefer to have my own header for every page… I couldn’t work out how to do that, but I have made a page template which allows me to use my own header image for every page apart from the home page 🙂 The problem I’m having is that on all those pages using my new template, I’m having a small issue with the top menu. Everything is okuntil I scroll down, then back up again – when I get to the top, the menu disappears. If I scroll back down again, it reappears, but I would love to fix this issue if anyone has any ideas?? Thank you in advance 🙂

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