Nedbank request for a refund for a client under debt review

I am very unhappy with Nedbank, I have two loans and one credit card with them. I went under debt review in December 2020. But they are the only bank I am owning which debited on my account R8644. So I paid the reduced amount and also the usual debit order I used to pay before I went under debt review. It been a month asking for a refund because I could not understand why I paid twice while I resorted to debt counseling because I was over indebted. I could not pay for my insurances, food, petrol e.t.c because of this. I am so disappointed with Nedbank