@markpousee have you already set the proxy server as a Trusted IP on cloudron - https://docs.cloudron.io/networking/#trusted-ips ?
Though, I cannot think of why nginx is automatically restarting . TBH, I have never seen nginx crash. This makes me wonder if something in your setup (compose?) is monitoring nginx responses (some healtcheck?) and restarting nginx automatically ?
If you have a test Cloudflare, you can quickly put Cloudflare in front of Cloudron and check if that works. After all, your proxy is same as Cloudflare functionally.
