nedbank atm query

On the 16 of october 2021 i received a nedbank cardless withdrawal of R2050..i went to the atm to redeem my voucher..the cash did not come out ,a slip came out saying institution not available..i thought maybe the atm was out of cash..i went to another atm it was saying voucher already used..i called the bank the said its an error on the first atm the money will be send bank to the account holder who sent you after 32 working days ..up to now nothing has been returned im always calling nedbank and they will say after 3 days you will get back the money but nothing..please help me what should i do..