Comments can not be left–error 403

It is not just this page, it is ALL of them. They have worked fine for a long time, and now, all of a sudden…..I have not installed any new plugins. I DID update to the newest WP which is automatic. I am no code jockey, my experience is limited. I use the theme Blogger Era but it has not updated lately to my knowledge. So why now, all of a sudden, does anyone who tries to fill in a comment get the 403 error? I have read tons of material but most refer to a specific plugin. As I said, I have not installed any new plugins. I suppose I could upload a backup and see if that works. Any ideas? Thoughts? Thank you!

The page I need help with: [log in to see the link]