Navbar does not interact when scrolling up

Hi, I’m wondering why my Navbar does not interact when scrolling up in which when its position is at the middle of the page. Which means I have to scroll back up until the top of the page that the Navbar will only interact. And this only happens on the 2nd and 3rd page. Is there any way to fix this problem?

Read-only link: https://preview.webflow.com/preview/qka-consulting?utm_medium=preview_link&utm_source=dashboard&utm_content=qka-consulting&preview=2d6ebf4db230fc14a9ec259b87d9edda&mode=preview