Large Debit Order Deducted

I was unemployed in 2019 and made arrangements of R500 pm on my loan and it was been debited,in the month of MAY and APRIL i noticed the amounts was not debited so i called the call center to find out whats happening and the consultant advised he will get some one to call me back..nobody done so, Due to covid i lost my contract position at my current company and now work as a free lance deisgner earning very less to to keep alive,i earn a salary of R8000pm and this morning an amount of R7248 was debited by Nedbank thats a full installment and half and that has caused a massive issue due to other arrangements taht was made for child maintenance been stalled and credit card not been paid....I did call the call center to query whats happening and waited on the call for 30mins and was told to call other numbers i spoke to Nicole then to Vinisha and finally to Suhad who notified me that the arrangement was only till april,I questioned why i was not contacted or anyone reverting to my call and worry that i was not been debited he stated that some tried calling in MAY but i never got a voice mail or a email or sms stating to call Nedbank to rearrange a payment...This has caused a stress in this trying times and i urgently request a refund please as i am in a bad situation. Pleae assist URGENTLY!