Thanks for reaching out.
I appreciate you sharing a screenshot of the space you would like to remove as that is super helpful! Could you let us know which theme you are using? As this context will allow us to determine the next steps to removing the white space that is appearing towards the bottom of your store. If you are unsure about which theme you are using, you can navigate to the Theme Editor and select the three dots located in the top left of the page. I took a screenshot from my test store to show you the section I am referring to:
Looking forward to your response.