Fraudulent debit of account without my authority - Consumer Complaint for AVIS RENT A CAR - HEAD OFFICE

I went to avis isando on the 28th of august and swiped with my nedbank cheque card for 2 amount of R530 and R3861.00 for the rental and the transaction went through it was approved and i have the slips on the 1st of Sept 2020 a amount of R3861.24 and another R90.00 went of my account with the reference Avis but i did not approve any debits on this account i spoke to nedbank and they said avis must reverse the R3861.24 and the R90.00 immediately as this is fraud