My main site is hosted in Vultr. When you access the site by IP Address it shows up with no problems. When you access the site via domain name, I get the error 521 from Cloudflare.
I added the Vultr IP to Cloudflare on Friday morning, it should have refreshed by now.
Domain: https://www.pdg-tx.org/
IP: 107.191.44.198
So since I know the site server is running, (nginx) because it responds to the ip connection, then what else can it be causing Cloudflare to think the web server is not active?