Complaint about expired goods

On the 10th of March 2021 I purchased a product Danone cultured buttermilk which expired on the 3rd of March 2021 and it was still on the shelf, when I took it back to the shop l was told the product merchant will come back to me but I didn't buy the product from the merchant or your supplier why must l given the run around. till today pick n pay customercare service is ignoring me after my complaint