Cancellation of insurance

Been calling vodacom for weeks to cancel the phone insurance***)which i was told will get feedback in 48hrs which i waited a week no Feedback then again i phoned to find out if the insurance has been cancelled all to find out it wasnt then requested the insurance to be cancelled again was told to wait 48hrs for an sms till to date havent received anything just wonder why should it be a problem when am cancelling the insurance,actually how many times should one call to get the help they need