Unable to connect to routers portal orbilogin... on initial setup

Model: Orbi CBR40, FW: Whatever came on Device I just bought. OS Windows 10 or iOS 14.02 for OrbiApp

I am not aboe to connect to OrbiLogin management site after connecting only main router-modem to existing home network with xfinity cable modem-wifi router.

I did the following steps:

-Connected Oribi main router-modem to a switch-to xfinity modem via Ethernet

-Connected W10 laptop or iPhone via  Wifi to ORBI's   SSID with password provoded on its label.  Observed Connected and Secured in properties.

-Verified client devices are able to access internet sites (E.g. this support blog).

  Observed wifi connection property: SSID/5Ghz/ IP 192.168.XXX.131, Gateway IP is pingable. 

-Cleared cache in Chrome, tried to access orbilogin.com or.net  

PROBLEM: When navigating to orbilogin.com or orbilogin.net get frowardeed to  Orbi Login (netgear.com)   page say8ing "Looks like you’re not connected to your Orbi’s WiFi network. Don’t worry, it happens to the best of us. Try the following steps to get connected:"

Note:

I have not yet approached xfinity to as my goal is to verify that ORBI system works with all my home devices. Recall, my main concern is that several devoices like thermostat, doorbell camera supports only 2.4GHz. So I'd like to test they work without any wifi bouncing before forklifting comcast wifi network. 

I was looking for general guidance, but will try findimng specific ORBI CB40 section I did not see before.

Thanks