New Panoramic Wifi broadcasting two networks?

Just set up my Panoramic Wifi (Technicolor CGM4331) and configured it to use the same network name/password as my prior Orbi mesh network. I have turned off all Orbi devices - the only modem or router in the house now is the single CGM4331 device.

Most of my devices automatically connected, which is why I chose the same name/credentials. No issue there.

My mobile devices now see two available wifi networks to pick from: One using the old network name (we'll call it OldNetwork) and one labeled "CoxWiFi". Both are showing as WiFi6. Both disappear if I turn off the CGM4331. OldNetwork shows as secured, and I have to put in my password to access it. CoxWiFi shows as unsecured, however it wants me to log in with my Cox account credentials to access it. Both appear to have similar speeds per the mobile device settings, and neither is labeled 2.4 GHz or 5.0 GHz which was my first thought.

Why is the CGM4331 broadcasting a second identical-seeming WiFi network under CoxWiFi name with different login settings from my existing "primary" WiFi network? How do I shut it down/secure it/combine it with the existing network?