Hello,
This is because of the default Margin and Padding of the WP Bakery Columns and Elements, you have to set the padding-top of the Inner Column of the Block to 0px and also you have to set the margin-bottom of the element to 0px and save changes and check your site after removing the browser cache, I am sure it will solve your issue. Please see these screenshots: https://prnt.sc/p0lpxi & http://prnt.sc/p0lqq4
Best Regards
