WPA2 settings

My Gateway keeps defaulting to open even though it indicates on XFi it has a password. The WPA2 light on top of gateway isn’t lit. How do I ensure it is set correctly & stays that way? It’s a ARRIS model TG1682G. I had previously set a password for the router itself since it’s default was the standard “password”. I’ll need to check that is still set. Help. Ready to cancel this service