Modem issues with Apple Airport Exteme

I have an Apple Airport Extreme w/2TB drive.  it has been ethernet connected to a cisco modem.  No issues, worked fine.  I receently upgraraded my package with Cox to the 3yr price guarantee.  I nnow have a Ubee 326B modem/router.  it does not recognize my Airport.  I have rebooted the modem an the Airport extreme several times, to no avail.  The technician was not sure of the issue and those he called were also not sure what should be done.  I need help.