Circle support on RAX70 router - App says "Darn, couldn't find Circle on your router", can't enable

(The drop-down box for "Model" does not offer my Tri-Band AX8 RAX70 model as a selectable option).

Hello,

I'm trying to get Circle parental controls working on my RAX70 wifi router. I am using what appears to be the latest firmware, V1.0.3.92.  I have installed the "Circle first gen" ios app on my iphone, which is connected to my home network.  I made sure to enable "Local network" access for the app and double-checked in the ios settings for the Circle app.  No matter what I do, the Circle app tells me "Darn, couldn't find Circle on your router".  Can anyone provide some troubleshooting tips on how to get this configuration working?

According to netgear, my router is supported:
https://kb.netgear.com/000044718/Which-NETGEAR-routers-support-Circle-Smart-Parental-Controls?language=en&utm_campaign=contactus_postsales_RAX70&utm_medium=websiteinternal&utm_source=contactus

I've read various different articles on similar problems; people have mentioned enabling/disabling parental controls in the router configuration menus.  I see no reference to parental controls in any manner whatsoever in my menus.

I know that my model router was not originally included in the "supported" list.  Does this just not work?

Any help would be appreciated.

Thanks,

Paul