The description on this error page reads:
You've requested an IP address that is part of the Cloudflare network. The request's Host header does not match the request's TLS SNI Host header
Most modern HTTPS clients send a Server Name Indication as part of the TLS handshake, when this name does not match the HTTP request's host header, a Cloudflare Error 1013 is presented.
The most common reason for seeing this message is if your local machine or network is proxying SSL traffic. Some SSL proxies have implementations that can cause an inconsistency between the SNI and the Host Header.
One useful way you can test whether your machine or connection is sending mismatched information is to visit an online tool such as:
This will provide a report of the SNI that was sent, if everything is working correctly the "SNI information" section should read: