Bad service

Sunday at Pnp Vangate Mall my daughter daughter bought a Cell C what's app bundle. She didn't punch it in due to her phone dying while we were at the mall. When we eventually got home she realized it was the incorrect network. We tried rushing back but the store had closed already. The next morning I called 4 times to the store and didn't get an answer. I then called Pnp customer care. I explained my delema. Then I was placed on hold for a few minutes. The lady then got back and said I can go to the store and the problem will be sorted. When I got to the mall I was told by the teller at the kios to come on the day the lady work who did the transaction. I said I didn't think it was fair because the mistake wasn't my daughter's. Now I have to spend money on airtime and petrol to sort this out because I'm being sent around. I told the teller I run a soup kitchen an I'm busy so I can't keep coming back isn't the something she could do. And she gave me a straight NO!... the other lady should fix it because it was her mistake. Yes a mistake was made and my daughter is at a disadvantage. And as her mother I just want to help her fix this mess. So my question is Where is the customer service??? I'm very disappointed in the level of service.