I don't know of any real troubleshooting steps to take. The app has very little in the way of settings. I know it is being invoked. It just isn't displaying anything but "UNKNOWN NAME" for calls it can't identify. And, I am not seeing any spam classification any longer. Mostly, I see "UNKNOWN NAME".
I think this has been going on for one to two months. As to whether or not there was an update, I'm not sure. Updates to apps happen frequently, so I don't pay attention to which ones get updated each day.
In any case, since the first response to my question was so bad, I have cancelled the service, disabled the app, and downloaded something equivalent from the Play store to replace it.