Airtel — UPC code not generating

I am an airtel postpaid customer with mobile no. [protected]. I have been trying to generate UPC code but not able to do so. Then I sent a complaint through email and twitter to Airtel India and they told me to pay a one-month advance rental to generate the UPC. I did make payment for a 1-month advance rental and tried generating UPC but without success. Now today I received a call from airtel saying that I have to send my documents and photograph to generate the UPC. As far as I know, there are no such guidelines to submit documents for UPC.

I even tried the Telecom consumer complaints system. But unable to talk to your complaint center on mobile [protected] because there is no option to talk to customer care

Kindly resolve the issue at the earliest