First off the the ax12 will not go online if you have other devices connected to the cm1200 modem. It has to be only connected to the router. Is that normal? Next if the internet is down for more than a minute the router must be factory reset to go back online.
1. The cm1200 has 4x ports. Sadly the ISP's and netgear do a poor job of explaining that the average user can only use 1 port (2 if using wan port aggregation). reason why is the isp's only allow 1 public ip address unless you're on a business class line or pay for more. And most don't. So only 1 port being usable is normal.
2. AX12 isn't the model number. What router do you have?
3. What firmware is on it.
4. Are you actually factory resetting it or just rebooting it?
I would try version 1.0.1.128 of the firmware. installi t over a hardwired connection and then factory reset and do a clean reinstall afterwards. (not from backup). this was a fairly solid version of the firmware. maybe the one you're on intruduced issues.
