The blog comments are not working, and it appears that Weebly (the company that hosts this site) is working on it.
More info is in the post linked below on the Weebly community help forums, hopefully they will update it when they have it fixed.
https://community.weebly.com/t5/Site-Editor/Site-visitors-not-able-to-post-comments/m-p/102391#M18134
Update 6/9/2018 - the Blog comments appear to be fixed so please feel free to post any comments.
More info is in the post linked below on the Weebly community help forums, hopefully they will update it when they have it fixed.
https://community.weebly.com/t5/Site-Editor/Site-visitors-not-able-to-post-comments/m-p/102391#M18134
Update 6/9/2018 - the Blog comments appear to be fixed so please feel free to post any comments.