Airtel — statement of inactive number

Address:

500079

We requested our nearer airtel retailer to port my docomo number to airtel prepaid. But he ported to airtel postpaid.

And my unused ported airtel postpaid number has billed with 900 for one month and we did'nt got any statement in post for what i have charged 900 and i called to customer care and asked to mail the statement, they confirmed me that they have already mailed to the email what they have and is not mine. And in second month got call for alternate number to make me know my postpaid airtel number is inactive and to pay the bill of 1200, i asked them to provide the statement of 1200, they said me it is not possible to know the statement of inactive account.
After few days i got call to my alternate number to "pay bill of 1528 or else we will file case and you need to go to court and your alternate number will be disconnected for this silly reason better pay the bill".

Is this the way airtel earning?

I need statement of my inactive airtel postpaid number. If i got the statement sure i will pay the bill for waht i used with late fee