I keep getting this error message:
Communication Failure: The computer is no longer able to communicate with your printer. Turn the printer off, check your printer connections and check for printer errors, and turn the printer back on.
If you followed the bold text in your post, with no change, either the printer has died, or your upgrade to Catalina has rendered the printer drivers inoperable 32-bit code. You will need 64-bit printer drivers to support this device on Catalina.
What is the exact HP printer model? Have you checked on the real HP support site for printer drivers or their HP EasyStart app (e.g. June 2020) that may locate Catalina compatible drivers for you?
Hewlett Packard Printer problem
