As @slashzero@hakbox.social said, if you’re using an additional nginx server, your docker nginx can’t listen for port 80 or 443. Here’s my host nginx reverse proxy’s ssl section for reference:

server {
    server_name kek.henlo.fi;

        location / {
	proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";

        include proxy_params;
        proxy_pass http://localhost:9001;
    }

    listen 443 ssl http2;
    listen [::]:443 ssl http2;
    ssl_certificate /etc/letsencrypt/live/kek.henlo.fi/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/kek.henlo.fi/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot
}

Maybe you’re missing some proxy headers, or the docker compose isn’t forwarding the correct ports.

But it can definitely be something completely different.

The other one has just copypasted the sidebar from reddit