New Modem not connecting to the internet

Just received the upgraded modem. Since I already had a modem, this process should be a simple plug and play.  It has not been.  I only use Comcast for internet.

I connect the cable coax, an ethernet cable directly to a laptop, and power supply.  Get all white lights on the front of the new modem.  However, there is no connectivity.  US is flashing. 

I then put the old modem in line.  No problem, all works well.  

I also have used the wifi, which the laptop can see and I logged in.  Still no internet connectivity.

1.5 hours later I am frustrated and using the old modem are posting here for help.

Thanks