Nike Shoes I Bought from Deichmann Burst in Months and Was Denied Return

We bought Nike brand shoes from the Izmir Optimum Deichmann store on September 7, 2024, and before six months had passed, they burst from the sides. When we took them to the store, we received a negative response. The Deichmann store evaluated the issue through its own employees and claimed that it was user error. However, the damaged part has nothing to do with user error. During these five months, the shoes were worn for a total of only two and a half months. How could this be my fault? Even the inside of the shoes is as clean as when they were first purchased. I expected better durability and after-sales support from both Nike and Deichmann. I want this issue to be resolved properly.