Hi there,
this really is a question for Elementor support but the issue is because you have used the Stretch option in the Elementor section settings. Instead of that use the normal full width section.
But first create a new Layout Element:
https://docs.generatepress.com/article/layout-element-overview/
In the Content options set the Page Builder container to Full Width, and then set the Display Rules to the pages where you want full width sections in Elementor.