I love the netgear modem, the indicator lights on the front can tell you a great deal. When you lose service, the top 4 lights, are they out, is light 1 on, and light 2 blinking? The lights, 1 is power, 2 is downstream, 3 is upstream, and the 4th indicates full sync, so depending on which lights are solid, and which ones are blinking, can help in ascertaining exactly what is taking place.
Also, i have the RAXE300 netgear router, and have noticed occasionally, it requires being rebooted for my internet to work. The modem, (CM2000) will indicate 4 solid lights, and the Cox app indicates no outage, so I restart the router and I am back online. I have notified Netgear about this issue. You would think that a router as nice, (and expensive), as the RAXE300, would be free of such issues, as my old Arris DG2460 WiFi Modem, NEVER had a problem like that and would run for months and months without issue. I have to reboot the Netgear router at least once a month.
Take a look at the lights on the modem next time you lose connection, let me know what it shows, and I can provide you the correct information to contact Cox with and get things working.