Vodafone India — unwanted subscription

My balance got deducted in the name of some healtho fortnightly pack inevery 15days even when didnt subscribed to any such service. This doesn't stop evn after i requested to stop this. Called this stupid customer care, they did confirm to received my call and message to their said number but still the requests was not generated hence they deducted the amount.. I dont remember clicking any link to activate such service but the executive was saying tht i did hence it got subscribed. My question is can u simply activate a service without confirming that action with the consumer by randomly sending such links in sms.. And that too from a third party. Also why are ur systems not upto the mark that they cant take simple stop request.. I tried doing that with both call and message means.. But it went invain