white space under the footer

no one knows?

Typing in capitals, shouting, does not make your thread inviting. Just so you know for future threads.

Here is a global technique used for getting your footer down to the bottom: https://matthewjamestaylor.com/blog/keeping-footers-at-the-bottom-of-the-page

If you don’t have the HTML structure in your theme as specified by the tutorial, you will have to make modifications to your theme’s files. Talk to your theme’s vendors about how to go about this, you’re not using a theme we support.