FNB THAT CANNOT HELP U

i went fnb centurion branch to reverse debit order that i did not authorize all in all it is about R2000 they have deducted in four amounts of R500.The guy at athe reception told me open my fnb app and login he said it will take about 10 days refund me back he told log in under Covid19 was so confused I am not applying for Covid relief fund I am talking about the money that was deducted on my account even last month they did deducted but I managed to reverse after too much deliberation or fighting.Please help to reverse that amount of R2000.00