Edgars
Billed twice but not refunding

I bought clothes for R449.95 and asked to use my points- the cashier did not subtract them. So I asked her to do it again. She did a new transaction for R403.95 but forgot to reverse the last one. She did a mistake and instead of reversing the last one, she redid the original transaction. She realised the mistake and only refunded the one transaction- not both. She was a trainee.
Therefore I was overcharged R449.95 as I did pay the correct amount for my purchase which was R403.95.
Please refund the R449.95 back into my account.
I have emailed the accounts department numerous times with no proper response.