debit order date not changed

I basically contacted cell c 3 months ago requesting that they change my debit order date to the last day off the month. Well last month the debit order went off on the wrong date meaning that my request was not actioned. Due to the fact that i had no funds in my bank account on that specific date, one of my contracts wasnt paid and the bank charged me R116. I then contacted cell c and a lady by the name of Ntombi Masinini condirmed that my debit order date wasnt changed on the system. Ntombi then confirmed that she will change it immediately and confirmed that her supervisor would contact me. That never happened!!!. I phoned again the follwoing day and was helped by a guy by the name of Smanga Makganga who to my suprise told me that my debit order date was still not changed and that my case was not escalated. He then proceeded to change my debit order date and provided me with a reference number for my case. Now cell c..who is going to pay for my bank charges and can someone get back to me. One of my contracts has still not been paid!!!-