Redirection not working anymore

I have used Contact Form 7 for many years, and I just realized that within the last month or so, the redirection has stopped working. I have tried everything to make it work. I have the correct code in the additional settings, but I just can’t get it to go anymore. I’ve been working on it all day.

For example here: http://www.sumydesigns.com/contact/

It no longer redirects. It used to work just fine. I have disabled all the plugins and tried it, and it still does not redirect. WordPress and all plugins are up to date.

Help?

https://ww.wp.xz.cn/plugins/contact-form-7/