Emily M. without the sandbox link, hard to say exactly but when inspecting the code, it looks like you've got a margin-top: 4.5rem on .section_sample-holiday_hero-header - it looks like there is a height calculation on this section that is accounting for the min-height of the navbar - but if you wanted more of this hero photo to show, I would actually just have it be 100svh or 100dvh without this calculation.
You're basically compounding these two things since the calc is already accounting for the navbar, and then in addition you have margin-top also trying to account for the same navbar. Would just revert both of those things and things should settle in how you would expect.
If I'm way off base here, feel free to send the sandbox link so I have the full picture.