[Resolved]  Airtel Mobile Postpaid — Refuse -issuance of receipt

I have approached to the Airtel Showroom which was situated at Perundurai road, Erode, Erode district, Tamil nadu State, on 2nd May for my payment to my 3 mobile numbers which comes around Rs.3500/-. The person at the cash counter told the receipt for the cash payment was not provided by the Company and they are unable to issue cash receipt if they accepted the cash. Hence i return back not to make any payment for the charges levied for my mobile phones.How can I pay cash for the bills without receipt?. The company may give clarifications.