This is usually caused by a misconfiguration in NGINX.
Hey there, by checking those commands I couldn't really get any insightful information, the nginx one game me the following output
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
Firewall and active services are out the scope of Webinoly.
What firewall are you using?
To know what services are currently active use service --status-all, you can find this kind of answers very easily in Google.
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