Allow Comments Box Checked But People Can’t Leave Comments

Hi:

I have a mysterious problem. On many pages on our site (such as the three listed below), we have the “Allow Comments” box checked on the “Edit Page” screens, but when you go to those pages, there is no way for people to leave comments (the “Post a Reply” box that used to be there seems to have disappeared).

If someone has insight into this, I’d much appreciate it. Here are the sample pages:

https://www.stopsexistremarks.org/post-your-ideas-for-responding-to-sexist-remarks/
https://www.stopsexistremarks.org/take-action/
https://www.stopsexistremarks.org/general-comments/