Airtel — balance not credited after prepaid recharge for 10 days

I did a prepaid recharge for my prepaid number on may 21, but the balance is yet to be credited in my account.
After trying for more than 1 week, airtel's facebook chat service mentioned about the amount got deducted for "value added service".
I never activated any value added services for my end. They have deducted money without consent which is very disappointing.
Moreover, i have been trying to reach out to them through ivr, mail but nothing seems to work.