Many reasons why..
When you ping the connection to the Ctrlr Site you will see it passes a few servers. You do not make a direct connection. It goes from one server to another to another to another and then reaches the server where the Ctrlr site is hosted. Now depending on how fast the provider recognizes that a certain server is down, the connection gets restored or routed to another server to reach the same end.
In that case, you’ll see that you might not get a connection with a landline but you can get a mobile connection or vice versa. The same goes for the provider that your friend uses might be different from yours thus avoid that server that is down.
You could even try a VPN because it makes a whole different route than your provider does. You could even try google translate (uhuh!!) and set languages from English to English, because google translate routes the website over its own servers. (And funny enough, that gives a 404 as well at the moment).