photo do not appear on the home page of my blog

I’ve installed Newspaper Theme for Wordpress. I read all the
documentation and set it up as it said. But all the images are not showing on
Home Page as featured images. I already checked and the images are well set on
each post. i have installed demo etc…i have done all manner of things still does not
work. I think that this could be a php problem but I am not familiar with it.
Could someone help me with that? blog url or direct link to see you can scrol down to POPULAR POSTS