Hi @hauzz,
I just checked locally, if you go to theme options -> general -> Fixed Navigation Bar, most likely yours is enabled. This means your Navigation Bar is fixed in place. If you disable this setting you can see it works correctly.
If you want to keep it fixed to the top and use our pushdown template I would suggest Rogier’s solution by making some room for the Cookie Banner until someone hides the banner by giving consent. But you will have an issue with your fixed navigation banner as it shrinks when scrolling, which makes the 70px difference with our banner a variable when scrolling the page, creating a gap.
For the gap: https://shiny-elk.w5.wpsandbox.pro/
I would suggest either a non-shrinking fixed header or a push-down with the above elements, with the soft cookie wall option enabled, so consent needs to be made before interacting. Or we will have a look at complementing all wishes, but this might take a while.
regards Aert