Poor Service From Online Shopping

I've recently had surgery which has necessitated my making use of Pick n Pay's online shopping. Among other things I purchased some chocolates that were on special. When they arrived on Monday they were completely melted in the heat. Almost liquid! I told the driver & showed him. He said he can't take the goods back as he is just a courier. I wrote clearly on the delivery note that this had happened. I also immediately emailed Pick n Pay's customer service to report the problem. By yesterday morning I still had no answer other than an automated response. I emailed again. Still no answer. I'm very disappointed with this lack of service. The chocolates should have been in a cooler box & not left in a hot car in a heatwave. It's common sense.