Three months, eight interactions, no change

Today I received a notification saying that I owe Vodacom money, presumably because my debit order bounced.<br> <br> A few things:<br> I have been trying since January to have my details changed<br> I have confirmation in writing that my details have changed<br> I have warned Vodacom, in writing, that these details have changed<br> <br> So how is it possible that after e-mails, online chats, phone calls and social media interactions my debit order did not go through?<br> <br> I'd like to know where Vodacom gets the audacity to send me these messages when the fault lies squarely on your side. I also feel it massively insulting to to threaten to cut my service off when you have confirmed, via telephone and in writing, that my debit order would go off as planned.<br> <br> You will do two things: switch my details and debit my account; reimburse me for the penalties my bank would have charged for the debit order.