Bad Customer Service

My name is Granny, I have purchase two school shirt and other things @ Pep Westgate. the shirts were for my son, only to find when he put a tie on them it doesn't sit well. unfortunately I had to take them back and I have misplaced the slip. Yesterday I went to Jabulani Mall. I spoke to the manager by the name of Kgomotso, explain to him I don't have a slip, but I have records on my phone which is bank notification. He was less interested very rude, I ask for his name of which his name tag was not showing, I was very disappointed.