No success of canceling debit order

I have requested from Vodacom on numerous occasions to send me the form to cancel my debit order as my bank account is inactive. They have promised me each time that they will email me the form to cancel my debit order so i can make my payments via EFT. NO ONE has sent me my form, i was now fined with a R100 because of the debit order being unsuccessful. It is the 25th today and still nothing, now i am going to be fined another R100 for the debit order not going through. I will NOT pay that fines as this is NOT my fault. I have spoken to them on their live chat facility, phoned them yesterday again when the phone call was dropped in my ear! This is unacceptable! Can someone send me the form to cancel my debit order. And make a note that i will not pay those fines as your call center staff and accounts department does not do their job!