Absolutely Pathetic Service

I changed banking details to Nedbank account. Sent it to accounts department. End of month 1- debit order tried going off my old account. I noticed it was the 28th and no debit order went off my Nedbank - mailed again - no response. I get a phone call from Warren, saying that my debit order has returned - insufficient funds (clients were in my office). I paid immediately by EFT, sent proof & my Nedbank details AGAIN(before month end, payment was not late). Month 2. The debit order went off perfectly from my Nedbank acc - 2 days after... call from Zared - my account is in arrears by R6600-00 & Ariva will hand me over.I told him the debit order went through successfully.He bluntly said that it's not true.AGAIN sent proof. It will now be updated.Month 3 - 26 Nov, Zared calls- Debit order returned unpaid. They again used my old account. He said if I had sent Nedbank details, it would have been on the system. Did EFT immediately, sent the Nedbank details.Yesterday, I get an sms & email, reading:Good day Mrs Erwee.Your account was handed over to collection for amount of R6607.00,Need urgent payment today.Failure to pay we will proceed legal action and car will be repossessed.