Bluetooth settings show keyboard--but I don't have a bluetooth keyboard
I have a 2019 iMac running Catalina. Occasionally, when the Mac comes out of sleep, the keyboard is not responsive and a warning appears, telling me the Mac cannot locate a bluetooth keyboard. But my keyboard is directly connected via a USB cable, not via bluetooth. There are no bluetooth keyboards in our household. The list of devices in the bluetooth settings shows a keyboard "Connected - Charged." Is that the source of my problem?
iMac 21.5", macOS 10.15