Why doesn't the Z-axis motor of RDC8445S controller move in manual mode?

Hello everyone! CO2 laser cutting machine with RDC8445S control system, switch to manual mode, and try to control the Z-axis motor through the Z+and Z - buttons on the operation panel. However, no matter which button is pressed, the Z-axis motor never takes any action. Check that the power supply and wiring are normal, and the controller status indicator is also displaying normally, but the motor still cannot respond to manual commands. What is the reason for this? Thank you for any suggestions!