Dishonoured arrangement by Nedbank Home Loans

I made a repayment arrangement for Nedbank to debit my home loan instalment for 20th December 2024 which they ignored and debited on the 13th. I called their offices and I was told they are investigating and I’ll receive feedback on Tuesday 17th Dec which never happened. I’m very disappointed and this tempers on the trust relationship since I’ve honoured all my obligations towards them.