ISP DCHP not configured properly - ASUS router error message

Hello,  I just activated my new account for internet service and my router won't connect to the Comcast server.  I get an error message that the DCHP is not configured properly.  I see that this is a problem others have had recently and the fix was to send a refresh of some type to my modem, but I can not get through to technical support after hours of trying.  I need someone to tell me how to get this resolved.  I have tried the comcast trouble shooter and rebooted my modem (ARRIS surfboard SB6183 multiple times, but his has not resolved the problem.  Can anyone help??