Large amount Debited yet arrangement in place

It’s been a miserable year for all and I have lost my job and made a arrangement with Nedbank to pay R500 monthly for my personal loan,On the 11/12 I was debited R500 and today a amount of R4832,03 which has left me in a worst situation due to other arrangements made with other accounts that now cannot be fulfilled. I have had a conversation with a consultant this month stating that the arrangement in place should run till end of Jan 2021 till I can find employment as mentioned it’s been a traumatic year for all. I am humbly asking for the refund to be actioned and this not to occur again please as it is now stressful to intake and with a medical condition it can cause damage. Please contact me urgently.