No internet connection between Netgear personal router and xfinity ARRIS TG4482A modem

Hi - Until yesterday afternoon - had xfinity modem connected to my netgear X6 router for internet both wired and wireless.  Neither xifnity modum nor Netgear were working yesterday afternoon.  After calling comcast, I picked up up and installed the new xfinity modem. The home network is now working, however,  my Netgear though hardwired does not have internet.  Restarted, unplugged many times and "internet" light is not on and netgear wirless network is not available.  Almost seams as if xfinity security is blocking my router?  Any advice?