Quick Deformation of Adidas Shoes and Company's Indifference

In April, my children gifted me a pair of sports shoes from an authorized Adidas dealer. Despite infrequent use, the linings around the side air holes began to detach, and the heel linings became deformed. I sent them to the authorized dealer for inspection through their intermediary, and after three weeks, they returned with the claim that there was no manufacturing defect. According to them, I had not used or maintained the shoes in the manner they expected. I find it puzzling how maintenance or usage relates to the detachment of linings, I would greatly appreciate your assistance in resolving this matter. Best regards.