Worst Customer Service Experience

I've just had the worst experience at Woolworths Walmer Park. I purchased 2 bras on the 31st of December and both were charged at a higher value. I returned them today - and waited quite a while before I was served. One of the cashiers tried to alert Charlene (the manager on duty) that I was still waiting but instead of following customer service rules she rep**** that they will help me when they are done. The answer was not directed at me the paying customer but merely one to say you can see that we are busy. I continued to wait while Charlene finished off her conversation with the customer. Once she was done she said that I can come to the next till - no apology was given for the long wait. What I sensed was highly antagonistic. Clearly customer service is not at the forefront at Walmer Park. Furthermore the difference was only R60 but she decided to put the full amount back on my card and recharge at a lower price. Surely the pricing error was not my mistake and I really do not understand why this was not given to me in cash. Now I have to wait 2 working days before the money reflects back onto my account. Apart from having to drive back to the store to highlight the issue I was also met with the most disrespectful service. I also do not understand why the "free item policy" was not followed. Why would a company apply different rules across the stores many products.?