Problem forCancellation of a contract and ongoing debit

Telkom are unable to cancel my contract and they are still taking money via debit order even though the contract expired in April 2018. I went to the office to cancel the contract,when I was there one of the consultants said I must come again to cancel the contract.I went to.see them three times and they told me to cancel a contract it must be done online and that I should go onto their website.I said that I struggle with internet so one of the consultants took my ID and canceled the contract for me.And that it takes a month to be processed.In June I went back to Telkom because money was still being deducted even though contract was cancelled in April. I insisted on seeing the manager to adress this but the consultant kept going on with me. This money are still being deducted which I had to reverse as I need the money and I cancelled the contract in April.Now the bank penalised me with the amount of R500.The money was deducted again 25 September. I Phoned Telkom again regarding this and they said that the contract are still not yet cancelled. I really need help please.