Wrong product sold to me

I went to the Dischem cosmetic counter in Norwood Mall and asked the cosmetics lady for a full cover long wearing foundation. I have combination skin and was introduced to Coverderm immediately. I was told that it gives full cover and wears for 24 hours and is water proof. She said this will be perfect for my skin. I got home and app**** the foundation and found that firstly the coverage was light to medium and after 1 hour the foundation became patchy and was barely visible. It increased the oiliness of my skin and I looked shiny! I feel that she just sold me this product without having any knowledge / training. Can someone please get back to me as I would like to be refunded the R499.00 I spent on this product. Thank you