Airport taxi scam

Took the cab today andtold him the location. He started the ride asusual. Switched on the meter and stuff. Then came the twist when he dropped me off. The charge was off by some 400-500 rupees. I asked him for a printed bill and he said the printer doesn't work. He offered to give a manual bill. Once I told him that I'll report to KSTDC. He said pay your usual amount and off he went.