Telkom Mobile - Canceled but still took my money

On the 3rd of October I canceled my contract with telkom as it ended on that date. This was to ensure that no money gets deducted and that the contract including direct debit is canceled. However, on the 15 of November, Telkom deducted the amount of R658.00. No funds was available as they should not have deducted. Now I have bank charge of up to R200 because of this. I am not happy and want a refund for this amounts.