Cannot disable IPv6 firewall on Nighthawk AX2700 (CAX30)

[freelead]

I need to disable IPv6 firewall on my AX2700 WiFi Cable Modem Router (CAX30S) , because it prevents ZScaler from connecting and I need ZScaler for work.

I go to the admin panel (HTTP://192.168.1.1), Advanced -> Advanced Setup -> IPv6. I check the checkbox "Disable IPv6 Firewall Protection" and click Apply button in the lower right corner. The router reboots, but when it's up the Checkbox is unchecked again.

My firmware version is V2.2.2.2, and the router says there's no newer firmware available.

[FURRYe38]

What browser are you using? Happens with other browsers?
Had the CAX been factory reset and setup from scratch after newer FW was updated? 

Wondering if IPv6 FP can be disabled if IPv6 is enabled...🤔

Who is your ISP? 

[freelead]

Thank you @FURRYe38 for a quick response!

I tried Chrome on MacOS, Safari on MacOS, Chrome on Windows and Edge on Windows - the result is the same everywhere.

Yes, the router has been factory reset

My provider is Xfinity (Comcast) in Jersey City, NJ

[FURRYe38]

Let me see if we can get some additional information on this. 

Thank you for your information.