Deichmann Store Sells Defective Puma Sneakers

I purchased a pair of Puma sneakers from the Deichmann store in İstinyePark, İzmir. Despite rarely using them and never wearing them in rainy weather, the soles of the shoes developed noticeable splits between the sole and the leather. When I contacted the store, they instructed me to bring them in for a 10-day inspection, which I did. However, the expert's verdict was that there was no manufacturing defect. But what user error could there possibly be when you trust a reputable store like Deichmann and opt for a brand like Puma, paying a significant amount? It's incomprehensible that they refuse to exchange the clearly defective shoes. I intend to escalate the matter to the Consumer Arbitration Board. Instead of spending so much money on shoes, I wore them only three times, I could have bought them from the market.