Deducting call charges on international calls, even the calls were not answered

Location/place: Madurai

Name of company/service: Airtel

I had frequently calling uk for my projects purpose, while calling i felt strange things happening like airtel is deducting amount while the phone ringing and their call charges starts even before the call picked by the other end. i have complained twice nothing happen. for me its 12.50 INR for one call in a day, roughly i might lost 200 INR in a month. think how ethically airtel doing their business…..