The blue light of the headlight started to shine once and then stopped. Why?

hello, your situation is probably due to poor mouse line contact or poor USB interface contact.

connect this USB interface with other USB devices. If it is used normally, the mouse cable is not in good contact.

You can remove the mouse, cut it short, and then reconnect it. Pay attention to the corresponding colors of the four wires inside and wrap the tape around each wire to prevent short circuit.