Why the charger of the electric stairs climbing trucks cannot charge ?

Why the charger of the electric stairs climbing trucks cannot charge ?

Please do the following troubleshooting methods:
1) The charger does not light up: not connected to the power supply. Please confirm that the power cord is connected
2) The battery does not light up: Please press the battery button and see if the light is on.
And if it still doesn't work , please kindly take a short video for us atservice@tosupport.com to check the detail issue.