We are using airtel prepaid service for my mobile in chennai. I have paid 1 year payment for caller tune. After 6 months, i found out that there was a big advertisement was playing before my caller tune and no one is able to hear my caller tune. Hence i called airtel customer service and asked them to stop playing the advertisement before my caller tune but they have the complete caller tune. Also they did not refunded the remaining 6month caller tune charge which i already paid to my account. They did some confusion and refunding the money and also taken Rs 60/- additionally from my account without any intimation. Several times we informed this to customer service but there is no proper response. This is really non-sense. Airtel customer service is very bad.