Please ensure that you're using the USB-C cable supplied with the ICON3. Whilst ICON3 supports USB 2.0 charging. Newer USB-C PD chargers may not be compatible. We recommend using the supplied USB 2.0 A to C cable, which works with any USB port.
If ICON3 isn't charging with the USB cable supplied, then there could be a fault. In which case, please open a support ticket with more details about the issue you're experiencing.