Call 191 and ask them to cancel the service. And threaten them you will file a case if they does this again. My dad has railway issued airtel number. Since it's issued from office .. sending and receiving messages on that number is prohibited/not allowed by railways. But curiously dad got a message that caller tune has been activated and from then he's being charged 15rs every month. Called CC and that b!tch argued for 20 mins saying that you have sent that message yourself, don't lie and our systems are ****in fool proof and all that shit. Finally remembered that this was railways issued sim and told that b!tch to check their records. Finally she loded a complaint. ****ing scam this airtel!