Featured Image only showing in blog archive, nowhere else

Hi! I tried searching the support for this issue but I don't seem to find it. I just created my new website on Chique Photography and it works perfectly except for this one issue: the featured image in blogposts appears only in the archive. If I enable the header image for entire site, then it shows the same header as the home page in all posts (and it's also the preview image for all posts), and if I turn it off, it does not show anything (and the preview is usually the first image of the blog). https://tombertolotti.com/blog/reach-out/ Here's an example :) I feel a little stupid because I have a feeling that the solution is pretty in plain sight, but I cannot find it... Thanks in advance!