I enabled Cloudflare via the back end of cPanel. It shows active in my account. I have it set to flexible. I also tried full. I had it set to always use HTTPS and then I also tried not but either way my Wordpress installation is showing a default error page:
That essentially disabled SSL. Set it back to “Full strict” and make sure your server is configured for HTTPS and has a valid certificate. This is most likely the reason for the error you experienced, your host didnt configure the server for HTTPS.