I installed Enfold and Demo Import. Now, at a blog overview page, it says people can comment, but at the blog item itself, there is no comment option. When looking at “Quick Edit” at that blog post, Allow Comments is ticked, so that’s not the problem. What else could it be?
Did you try adding “Comments” under content elements in the avia layout builder? I was having the same problem as you until I realized I had to add that element within the layout builder… problem solved!