Airtel — cheating in plan and unreasonable charges in bill.

I port to airtel postpaid from other operator.
First they told me that plan will be 399 per month and we will give you 100 discount voucher. But in first bill there was no voucher. then they agreed for voucher from next bill.
Also with unlimited plan they charged me Usage charges of approx 50. When I asked they told me that you made calls on special numbers which are not included in plan. I want to know about those special numbers.
They also charged for some international messages. But in reality I did not send any messages to international numbers.
Please forward my complaint to airtel.
Thanks.