Access Point w/ Cox Panoramic

Hello, I am trying to add an ASUS router as an upstairs wireless access point to my house’s Cox Panoramic WiFi modem/router. I have set up the ASUS router as an AP through the browser settings but when connecting to its WiFi signal, it says ‘no internet, connected’.

The ASUS AP is connected via an Ethernet port on the Panoramic into one of its LAN ports. I’ve tried the WAN port on the AP but that also doesn’t work.

I do not want to enable bridge mode on the Panoramic as it serves as the router for downstairs and I don’t want to disable that function, is there a setting I am missing on either device? Thank you for any help!