Charger for failed debit order when I paid my account in time

Cell C did me dirty!!!! I have been their customer for years without any issues . It happen that this year I got very ill , I was diagnosed with critical illness I have to be booked off at work from Beginning of Aungust . I have made arrangements with all my creditors by submitting my medical records and proof that I wasn’t working. 1st month I paid at the store, following month I called them to assist me about payment arrangements they made it clear that they can’t assist all they want is their money after 3 months of not receiving money they will block my lines and take legal actions. So they suggested I make eft payment 5 days before debit order date so they automatically dnt debit me. I was given banking details and reference nr to use, I did that and sent proof of payment on the day. Only to be debited on the 26th and my bank charges me R105 for a bounced debit order. I called , sent emails , they told me the reference nr I used was wrong but I was given by them. I begged them on emails and and on phone calls not to debit on my account because there is no money. They ended up charging me R80 extra for a failed debit order. They allocated my payment but still debit the R80 that I accumulated by their negligence. To day I’m sitting with the negative balance of close to R 1000 due to their failed debit orders. I’m very sad because I have made all necessary arrangements with them and explained my situation on top that I paid my account only to be treated this way.