If you want to log into your LOCAL ASTROBOX, you are required to be connected to the same local WiFi network as your AstroBox.
The reason for this is, when your AstroBox is cloud connected, by definition -- there is no need for a user to access the local AstroBox. In fact, we discourage it because it can get complex with port forwarding / command line nonsense.
The second reason is due to security.
Why exactly do you need to access the local AstroBox when you already have it connected to your AstroPrint Cloud Dashboard?