Unable to Activate New Internet Modem

Existing modem works great, but does not have WiFi... so attempted to activate a new Internet modem with WiFi (Motorola MG7540)  - connected everything up and all channels show connected / bonded and online, but no success with online self activation, so called tech support and cox Internet support was not able to see the modem so unable to activate.  Supposed as an issue with the modem, so bought another brand new modem, this time Motorola MG7550 and same thing, all lights show connected and bonded but unable to activate online... tried calling in to see if cox Internet support could see the modem but was disconnected twice! after hold times of 12 minutes and then 18 minutes... so frustrating...

I don't have phone services with cox so this is not a phone modem.  Any ideas why i cannot activate a new Internet modem...?

Thanks.