Bad balloons

Last night I bought a packet of 10 balloons priced R14. 99. When I got to my car and looked at my slip, I saw it scanned as 100 balloons at R49. 99. Ridiculous. I took the balloons back and asked for a refund. When the lady tried to do the refund, the balloons scanned for R9. 99. Now here is where the drama started. They went to look at the camera footage to see if I actually paid for it. The security supervisor came and asked me "what is the problem", I explained everything. He said "yes, he can see I paid for it". I almost laughed. I said, yes I know I paid, but I want my money back. He didnt know what was going on. The manager apparently also did not know what to do. I was asked the most ridiculous questions, for instance, did I go home with my shopping and came back again. I was standing there for 45 min. In the end I got my money back but offered no apology. The particular shop is known for its wrong pricing and the manager never considered that there may be a **** running at the cashiers. I felt I was treated like a ********. And they were *********** in sorting it out. As a retail worker myself I would never treat a customer that way.