Incorrect debit order amount

I've been using telkom contract for same time now. I reversed one debit order and they cost me R200 for that and this month they took R400 instead on R100 when I called for reversal they said I should wait for 14 working to allocate than other 7 working days for refund. I'm totally annoyed. This is my money which I work hard for. It not what I agreed on. I need my money back within 7days. I'm so disgusted with them