RDC6332NM cutting head automatically searches for focus and moves downwards continuously

1. Contact the cutting head with a metal object and observe whether the collision indicator light on the amplifier and the indicator light connected to the height adjustment box are lit. If so, rule out any sensing issues. If the indicator light is not on, the sensor is faulty.
2. Check the wiring and board grounding issues.

In my opinion, the reasons are as follows:
1. Sensor or amplifier malfunction collision alarm wiring error
2. The metal plate being tested is not properly grounded to the machine