Unable to reach the ASUS router via the AT&T network connection
Unable to reach the ASUS router via the AT&T network connection
You're encountering an issue where typing 192.168.1.1 on your ASUS router redirects you to the AT&T modem/router interface instead of the router's settings page. Since you've managed to access the router settings before, consider checking the following: network configuration, IP address changes, or a possible misconfiguration in your device settings.
Because they use the same IP address. You should switch AT&T or move the ASUS to a different network. If you do that, the ASUS router will need to be set to 192.168.2.1, which will affect all devices connected to it.