Expired Stock Issue with Coca-Cola

I own a Pala market in Kepez, Antalya, in the Güneş neighborhood. We have about 10 to 12 boxes (each with 27 units) of small fruit juices that have gone bad in our warehouse. We told a lot of people about this three months ago, including the Coca-Cola sales manager in the field. They said they had sent emails, but there was no proof. They said this week that they would buy the products back for half the price. When we buy things, we pay for them with cash. Why doesn't Coca-Cola back up their product? Where is this so-called national company's sense of business ethics?