Problem with a gap under featured image

Hello,

there is a very big gap beneath the featured image on all my post pages. Even though I have not set a margin. So there basically is a very big gap under the pic until the actual article starts.
This problem exists in the desctop version and even more extreme on the mobile version. It gets worse the smaller the screen gets.

Screenshot: https://ibb.co/jdNSX7

fixed