Nedbank unacceptable service

I have a Nedbank loan account and they changed the debit order date from end of every month to 18th in January 2020 without notifying me first. The message notification on my Nedbank account where the debit order went off in also came late i.e. a day after. I decided to check my online account to check the transaction and then I noticed it was double debited which means my car insurance and other debit orders was compromised. I phoned the contact center and they took over 1 hour to process the refund and change back the debit order date to end of the month and I specifically told the consultant to start the next debit order at the end of February since this month is already paid for. He said yes things were sorted and the refund will be processed in 3 days or less. This is the third day and no refund has been received yet for the double debit order. I phoned the call centre yesterday to check that everything is in order and the lady helping me said that the next debit order date is 31 January - this is not acceptable because the bank would double debit my instalment again if i did not check up. I am still waiting for my refund so that my other debit orders can go through - will the bank be responsible if my car insurance is not paid due to this situation they put me in, the instance when I cannot claim my car insurance?

I am upset because this is incovenient to me as I have a system in place to ensure my other debit orders runs smoothly.