anchor back down to form if required fields not filled out

That should already be happening: the form outputs an anchor and submits with that anchor in the URL to push the screen down when displaying errors or success.

Have a link where I can see the issue?

https://brancatoscatering.com/box-lunches/

Its at the bottom of the page

Oops! That feature was broken. Fixed in 2.6.3.

I just downloaded this plugin last week. Was the fix done after that?

I fixed it yesterday in response to your bug report (aka this thread) — compare the version numbers (that’s what they are for).

??