network – Facetime audio calls not working using iPhone

I have a Netgear Nighthawk MR60 mesh system with a WiFi router and one satellite. Since I installed it, I cannot make calls using my iPhone xs with either of my Mac computers. The window comes up telling me I’m using Facetime audio with my iPhone, but I immediately get a message in the window saying that the phone and the computer must be connected to the same WiFi network in order to complete the call. Repeated attempts at this have failed.

It looks like everything is set up on all Apple devices for this to work.

On my Nighthawk app, all 3 devices show up on my 5 GHz network.

This worked with the former WiFi router I had and replaced. It was not a mesh system. That router had the ability to connect to either the 2.5 GHz or the 5 GHz network manually. Apparently, the Nighthawk does not have the manual connection option.

I’ve tried logging out of and back into Facetime to no avail.

MacBook Pro (Retina, 13-inch, Early 2015) running macOS Catalina 10.15.7;
iMac (Retina 4K, 21.5 inch, Late 2015) running macOS Cataline 10.15.7;
iPhone XS Max IOS 14.4.2

On the Apple sight I can only find older similar questions – nothing recent except what I posted there.

Any help is welcome and appreciated.