I solved my problem:
I have a Belkin WiFi Router. I reset it but I did not connect to the https://192.168.1.1/ configuration address to configure the router but instead used the password printed on the bottom of the router.
It seemed OK doing this as a 2016 iPhone SE on both 2.4GHz/5GHz, Samsung Galaxy A10e on both 2.4GHz/5GHz, and a Windows 10 Desktop on both 2.4GHz/5GHz all connected to it fine and the internet worked.
However as I said the Chime would not work.
I also had to reconfigure a ROKU MDL Stick on both 2.4GHz/5GHz and even though I could connect for both bands neither internet connection worked.
Therefore I connected to the Belkin Router on https://192.168.1.1/ and followed the directions the Belkin Router asked for my to do.
After that, my ROKU MDL Stick started working again on both bands the internet and I was again able to configure my Ring Chime on the 2.4GHz band. The Ring Chime I have has no 5GHz band. It now works again.
So, a somewhat deceptive problem in that some devices worked using that Belkin WiFi router and some did not using that Belkin WiFi router until I actually connected to the Belkin Router and configured it according the the instructions it gave me. I didn’t change any configuration data it had though but simply manually typed in the 2 names of the WiFi networks it was broadcasting and also the default random password it supplied printer on the router.
So if you have similar problems with your brand WiFi router, give a similar configuration procedure for your WiFi router a try.
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Ring Community Forum Software is falsely flagging my posts even though this solution I discovered and tested is the solution that works.