Airtel — wrong deduction of rs. 20 for bhakti sagar portrait

This is to inform you that i have not subscribed any bhakti sagar portrait but rs20 has been deducted from my airtel mobile a/c. Plz look after this matter to refund my money as early as possible. Money was deducted 15/10/2018. Without taking my permission money was deducted. So you are requested to please resolve my problem. I am a airtel customer for a long time and have not facing any problem till now. But this time it is happened very wrong to me. Please resolve my problem and refund my money.