NEDBANK Debit order System Issues!!!

Good day, Nedbank has placed in a bad financial position because Nedbank decided to deduct my home loan instalment on the 9/01/2020 which was supposed to be deducted on the 21/12/2019. Nedbanks debit order system instead Credited me the instalment and now wants to take money weeks later due to there debit order system not doing its job. When calling into Nedbanks offices, agents places you on hold and are so confused and I have to explain the same thing over and over!!! Nedbank please refund my money because it's not my fault your debit order system did not deduct my instalment when they suppose to. I'm using all my money calling Nedbank and no one calls me bac****