On the HP printer the date and time is not correct. Perhaps a Reset Factory Settings has been performed on the printer without setting the correct date and time. After a subsequent installation of Printix Go, Sign in fails and the printer’s touchscreen shows: The default sign-in method (Printix) is currently unavailable. The issue occur because incorrect date and time on the printer invalidates the used certificate.
RESOLUTION: Set the date and time on the printer to the current data and time.