Smart Forms stopped working

Have been using this form for several months without any issue.

Recently,

5/6/2021 the smart forms service stopped working.

https://tablerstation.bss.design/COVID-19-Visitor.html

The smart form works when sending from the studio preview, but fails to send after deployment.

Additionally getting “Web Site Has Been Blocked!” message when clicking on previous smart form emails from 5/6/2021

You seem to be running some type of firewall solution called proofpoint that is likely triggered by the covid-19 in your URL. You can try publishing on a different page/website.