By default, our header has a margin-bottom and if you want to remove it on your home page, you can simply add a negative margin-top for the first row on the page with WPBakery page builder. So just set -40px, for example, to compensate for it.
I managed to sort it out on the homepage however on the other pages I create it is still playing up, there is now a new white gap at the top above the header and then what looks to be a transparent gap below it.