No Dial tone with new Arris Modem Install

Bought my own Arris Surfboard with Internet, WiFi and Voice modem.  The Internet and WiFi work but no Voice.  The Homephone worked with my Xfinity modem but not with this new one.  Was on the phone with "Agnes" for over an hour; she said everything was good on her end.  Rebooted the modem numerous times, unplugged and plugged phone cable numerous times, switched phone cables and still no dial tone.