Coles Supermarkets Australia

Today the 6 th of Feb. 2020 at 5:10 pm I bought many items from Coles tea tree plaza I paid then discovered that I was charged for the plums more than the tag price, I went back to the service counter they said yes you are right then the paid me the difference between the actual price which was 3.50 /kg and the Charged price which was 4.90/kg which was 2 dollars plus, I said that I should get a full refund for the item she said now which I believe it's wrong Coles has a full refund policy and I had a full refund previously