Could you let us know whether the Wi-Fi network is broadcasting on your devices?

Have you tried activating the modem with the ISP?

I finally got into xfinity agent support. They activated internet account. But couldn't connect to modem. Spent an hour on it. Arranged for a senior tech guy to come out tomorrow and figure it out and sent record of all the work done during the chat

are you able to log in through the browser and check the cable connections page and event logs? 

Turns out that the xfinity cable from demarc post to house was defective. With new cable, signal came to modem which started right up with no problems. Xfinity had assured me that their signal was reaching our house.

They always say “our line is fine. It must be your device”. thats their first line response so they don’t have to send someone out