cannot get Post comments form to appear on my page

I cannot get a Post form to appear at the bottom of my page where people can post comments like it’s supposed to. http://www.beyourowndetective.com/blog/

I have spent plenty of time in the Admin trying to figure this out, and made sure I have “Allow people to post comments on the article” checked, and I checked elsewhere to make sure this function is enabled, but it still isn’t working.