XFI Pod Offline and wont reconnect

Hi all.  I have three pods connected to my gateway.  all three worked fine for a long while.  A few weeks ago, two came offline (not sure when or why).  I followed the troubleshooting (unplug, wait, plug back in).  One came back online, the other not.  I have been plugging and replugging in several times over the past few weeks but no joy. 

Any other troubleshooting suggestions? 

Do i have a dead pod?  does xfinity swap them when they die or do i need to buy another?

thanks.