Shocking lack of customer service

Went to Donna Claire, bought two jeans that were marked down from R429 to R279. Had a gift card for R300. Lady cashed up sale I paid using my debit card. As I walked out of the shop I checked my slip only to seeing paid R708. I turned back and asked her how that is possible seeing that I had gift card for R300 (not even realising I should not even have paid that much if you add 2 discounted amounts). Juliana (the salesperson) did not know how to fix it and proceeded to phone someone to ask how. After about 10min's she said she can only reverse it if I give a credit card. What if i didnt have one. Sales was eventually reversed (although not reflecting in my bank yet). She then put R408 through on my cheque account and used R300 gift card, only then I realised it an impossible amount as entire total should only be R558. Needless to say another reversed amount on my credit card (still not reflecting) and then had to put two separate transactions through as she didn't know what "was wrong with the system". NOWHERE did she once apologise, not for the error, not for wasting my time, nothing! I have never experienced such shocking service. I'm disgusted, and unhappy as all her errors causes me additional bank charges and wastes my time. And I sincerely hope those amounts are reversed seeing as I have now paid R1974 for two jeans shorts.....