1. The printer connection cable or computer parallel port is damaged, resulting in paper shortage prompt. You can replace the cable or the parallel port to troubleshoot.
The driver is wrong. You can reinstall the printer driver or upgrade the driver.
3. If the printing paper sensor is polluted, you can find the printer sensor according to the instructions and observe whether it is polluted by dust, so as to solve the problem that the printer paper tray 2 is wrong.