Checking the "Hide Featured Image" box leaves grey area on the page.

Please see attached to better understand this issue.
I have checked the “Hide Featured Image” box on the page with the following URL:
simultaneouslanguageinterpretation.com/aaa-carlos

However, this leaves a 70 pixel high grey area where the “Featured Image” would be if I had NOT checked the “Hide Featured Image” box.
How can I make this grey area go away?

Login info. is:
URL: simultaneouslanguageinterpretation.com

WP-Admin access:
User: [Removed]
PW: [Removed]

FTP:
Server/Host: [Removed]
User: [Removed]
PW: [Removed]
Port: [Removed]