Airtel — EDGE got activated without my permission

I have an Airtel Prepaid connection and my number is [protected]. Recently, the EGDE or GPRS has been activated without any prior notice. I did not apply for activation. I lost a lot of balance because of that. I request an airtel customer care executive to contact me on [protected], as i took out the [protected] sim card from my phone as it keeps on using the internet, decreasing my balance. I will be waiting for the call.