Online failure

I placed an order online for my son's school shoes and nearly waited a full week for the order to be delivered. On the day which it was delivered they provided the incorrect size, how do you confuse a size 13 for a size 5? I called the contact centre and spoke to Keranay at tygervalley branch who said she will call back, i can tell you now I am still waiting on that call. I asked what about the delivery fee that I paid seeing that I now need to go back to a store to sort this out and no one could answer me. I called 4 times today and guess what, still no resolution in sight. I am planning to escalate this to your CEO for **** service