[closed] [not resolved] Nginx addon and reverse proxy

Hi,
I’ve installed the NGINX addon and configured with hassio.example.com and letsencrypt certificate to point to my hassio server. This works fine. But when try to add a second domain to point to my qnap nas on a different machine from qnap.example.com, it doesn’t work.
I have created /share/nginx_proxy/qnap.example.com.conf

server {
    server_name qnap.example.com;

    location / {         
	proxy_pass http://192.168.1.15;
    }
}

But when I restart the add-on I get the following error:

[INFO] Running nginx...
2018/12/04 11:22:59 [emerg] 8#8: bind() to 0.0.0.0:80 failed (98: Address in use)
2018/12/04 11:22:59 [emerg] 8#8: bind() to 0.0.0.0:80 failed (98: Address in use)
2018/12/04 11:22:59 [emerg] 8#8: bind() to 0.0.0.0:80 failed (98: Address in use)
2018/12/04 11:22:59 [emerg] 8#8: bind() to 0.0.0.0:80 failed (98: Address in use)
2018/12/04 11:22:59 [emerg] 8#8: bind() to 0.0.0.0:80 failed (98: Address in use)
2018/12/04 11:22:59 [emerg] 8#8: still could not bind()

Is there something I’m missing? I’ve read to most of the nginx threads but I couldn’t find any working solution.

Finally I installed HAproxy on another machine as reverse proxy which allows me to use different certificates for different domains.