Page jumping when scrolling on iPhone Safari (only on certain devices)

Hello everyone,
I’m having a pesky bug on the website I’m working on that I’m not able to figure out.
Basically on some iPhones (mostly 13 and above) it seems like my page starts jumping around while scrolling. I’m not quite sure what happens but it feels like it’s related to the url bar shrinking. What do you feel is happening?

here’s the link to the homepage

thanks in advance for any help

Here is my site Read-Only: [LINK][1]