Please check again if the USB type-C cable you are using has the output of 5V/2A.
You can only use cables that have the above output.
Also, try using other electrical outlets and see if it starts charging.
If it does, the LED will blink and tell you how much charging left is needed.
If it does not start charging even when using other electrical plugs, try charging it using your own AC adapter (charger head) by connecting the adapter to the USB type A cable attached to the device.
For details on how to charge, please refer to the Quick Guide here.