I had a similar problem. My contact form using WP Forms would not send mail. I hired someone to fix the problem and they determined that SG Optimizer was the problem. Sure enough, the form worked when SG Optimizer was deactivated. Then I had someone try to fix a formatting problem with the form (font size). They activated SG Optimizer and the form stopped working. I deactivated the plugin and the form worked once more. The Contact Form may be the most important part of my site, so I’m leaving SG Optimizer deactivated for now.
