Airtel
Unnecessary deduction of my balance

I just typed a tollfree number on airtel and they chargesd rs 10 for that and englishguru was activated. i didnot use it and stopped the service. but my 10 rupees . my dad will scold me. just tell them to refund or else...
they should inform about the activation on dialling the tollfree number. they have not done so
please kindly help//
only refund nothing else...
i u want tell them to check my numbers activity history