There is something wrong with your CNG settings. My car does between 17-18km per KG of gas. For example i put 300 rs gas the other day so 300 @ 55.30 = 5.42KG. I got around 97km's from this. So 300/97= 3.09 rs/km.
Another way to look at it 5.42kg gas into 18km/kg = 97km
Whereas with your car you get 8.93kg gas into 10.5km/kg = 94km
So your car should be giving you at least 15-18km/kg of gas. Right now it's only giving you 10.5km/kg which is quite less for a 1.3L car. I have a 1.6L car with 16" alloys.
Could also be the fact that your car is almost brand new, i heard that after a little time the mileage of a new car improves slightly. Nevertheless, get the CNG settings tuned by a good mechanic.