I totally get how frustrating that error can be. I’ve run into a similar issue before, and in my case, it turned out to be a conflict with how certain themes handle AJAX requests in combination with caching layers and form plugins.
One trick that helped me was testing the form in a fresh environment (you can even clone your site to a subdomain for testing). Also, make sure your hosting environment isn’t blocking outgoing requests via mod_security or firewall rules.
Weirdly enough, I also once spotted this issue when I had a social media automation tool configured incorrectly on a client site. If you’ve got any third-party integrations or scripts running, try disabling those temporarily too.
For general performance and smooth plugin integration, we follow a checklist like the one we use for sites managed at buy follower maybe give that a peek for ideas.
Hope this gets you closer to a solution! Let us know what work
