Adidas Shoes Opened from the Soles After Two Months but They Refused to Replace Them

About two months after buying a pair of adidas sneakers, I noticed that the bottoms of both shoes have begun to separate in the same area. With the hope of receiving a fair resolution, I took them back to the 'In Street' shop from which I had purchased them. Nevertheless, it was informed to me that no manufacturing flaw was identified after inspection. This seems unbelievable to me, particularly in light of the obvious indicators of poor quality caused by the damage. How can something as obvious as wear and tear on shoes that are only two months old not be deemed a defect? This has made me doubt In Street's and Adidas' quality control; I'm hoping they'll own up to the product's flaws and find a way to fix them.