Problem: Sometimes a page will function correctly on desktop but in mobile view the drag/scroll will get stuck when the page first loads, continually bouncing back upward. Sometimes with enough tries, it will eventually let you scroll down the page content.
I’ve seen this bug posted quite a bit without a consistent answer to the question. Facing a similar issue, I was able to solve via the following:
Make sure BODY does not have any styles applied to it. Always the top suggestion; this helps avoid any overflow issues, max-height restrictions, etc.
Look for all top-level page elements that have BODY as a parent. Make sure none contain a negative value for the bottom margin.
Number 2 above was affecting a current site build for quite some time until the bottom margin was removed from one of the page container divs. I hope this is helpful for anyone else experiencing a similar issue!