FNB Bank ***** that cannot be resolved

I have been banking with FNB bank for ove 10years now, hence what I experienced last week is very heartbreaking. FNB claims that I have personal loans with them in June 2019 of R6800, therefore FNB deducted an amount of R1258.98 from my account twice end of November . I then requested for a despute and couldnt be helped, I even went to the nearest branch whereby I was asked to tellephone the dispute departement from the branch. Thereafter I kept on being on hold, spoken to a lot of consultants saying that the debit order cannot be reversed nor stopped. I was adviced by FNB to send my bank statement(which doesnt show the loan amount credited into my account) and ID copy to the ***** email. I have been wait for over a week now, nothing has happened. I am afraid my money will keep on going as I am about to get my next salary soon.