The error code 13.20 is a paper jam error.
- Remove the paper tray and the toner
- Check for any sheet of paper stuck in the machine
If you see any sheet of paper, a sensor may be stock or defective. Try this:
On HP Website:
If you still have the error 13.20, try this:
- Check for any foreign object in the printer
- Check the transfer roller.
- Replace the sensors
- Replace the roller separator
- Check the fuser unit is properly installed