Rear window heating

The rear window heating can be switched on and off by means of a voice command. After “back window heating is said to be, the command is also confirmed by the vehicle linguistically. The only catch is that the rear window heating is not concerned. If the rear window heating is switched on manually and then the voice command “back window heating is said to be confirmed but not executed. Why is KIA not able to perform this simple test itself and your software Don’t correct it?