Configuring Cloudflare HTTPS with Auto-SSL issued to domain by cPanel

As a last resort, I suggest that you Pause Cloudflare and turn on AutoSSL again.

Once that’s working, unPause Cloudflare and confirm you’re still getting the 502. Then you can Pause Cloudflare again and open a Support Ticket. They can simulate running your site on Cloudflare and can hopefully figure out why there’s a 502 error.

Login to Cloudflare and then contact Cloudflare Support by clicking on the Get More Help button.