How to solve err_connection_refused problem?

Question

Nginx

The site does not work fully on some devices. When I googled this error, I always found solutions in fastcgi technology, but I don't even have php. The site simply does not open and displays this error.
What could be the problem, in the ssl, in the cloudflyer in the nginx settings?

Answer 1

Any of the above.
Some server refused your connection. Due to settings, certificates or an error.