FNB DEBIT ORDERS

I was always happy with FNB until recently.. HOW CAN A BANK NOT DEBIT YOUR ACCOUNT AND NOW ITS MY FAULT???

In September 2020 FNB notifies me that I am behind on one of my homeloans AND my car installment. I advised them it's impossible as there are funds available and the other FNB home loans went off?? I HAVE A DEBIT ORDER! Only for the operator to advise me that FNB changed their "debit order system"? And that's why the debit orders did not go off. I am upset that FNB has now put this on my record when I GAVE MY PERMISSION TO TAKE THE DEBIT ORDER WHICH WAS NOT TAKEN.

PLEASE, is there anyone in FNB that can help me rectify this to not impact my credit score as it was not our fault!!

I've been trying to rectify the situation by calling and I've sent emails but nothing has happened yet :(