Cm1000 and nighthawk x4s. Loose connection to Internet requires a reset to factory default

The CM1000 is ONLY a modem. There is no built in router. 

Has a power off for 1 minute then back ON with the ISP modem and router been performed since last update?
Be sure to restart your network in this sequence:
Turn off and unplug modem.
Turn off router and computers.
Plug in and turn on modem. Wait 2 minutes for it to connect.
Turn on the router and wait 2 minutes for it to connect.
Turn on computers and rest of network.

What Firmware version is currently loaded on the modem and router?

Try connecting 1 wired PC to the modem and power cycle it. After the modem comes to ready can you get internet services thru the modem on the PC? 

Be sure your using good quality LAN cable between the modem and router. CAT6 is recommended. 

Please post a copy and paste of the modems connection status page.
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html