Formmail failure

I am working on the new version of a site I did five or six years ago.

In the interim, the client asked for a change in the contact page, and now I am getting an error I’ve never seen before (also on the email page). Evidently, there is an error in my formmail, but I can’t see what is causing the problem. Can anyone offer a useful observation?

The new contact page:
A duplicate of the formmail file, where it can be viewed:


I filled in the form. All I get is “Thank You.” No error.