It's doing it on every site in Brine 7.0. This is such a nightmare, I have clients constanlty getting in touch to ask when I will fix this, but there is nothing I can do, as it seems to be a Square Space issue.
The attachments are just a handful of my sites that are the same.
Form fields not lining up
in Site Design & Styles
Posted
I contacted Squarespace about this 3 days ago, it has now been fixed. It was a bug across all 7.0 and 7.1 sites using this block in this way.