UNHAPPY WITH SERVICES RECEIVED

In The month of August i have mistakenly added 1GB data on the top up contract that I have . Ever since that month I am trying to get someone to cancel it . I have called Vodacom customer care from August going till date and this data has still not yet been cancelled . I keep getting promised that it will be cancelled and will not reflect the following month but all that is lies as it still reflects and I am still liable to pay for it . I don't want my account going into arrears but i guess Vodacom does not care at all as long as the get they money at the end of the month . This is absolutely terrible and the worst experience ever , I will never recommend Vodacom to anyone .