I recently bought sneakers(

I recently bought Nike sneakers(Roshe) under the impression that there suitable for working out wich mainly I was using them for and now even two months old the right pair was damaged and it's not through any form of an object Turing it but simply just started unstitching, I went back to the shop to ask if they can look at the shoe and send it back to the factory to be checked if it's a factory fault cause for a Nike shoe it should last longer than it did and I was told that cause it was too late they only consider shoes if it's a day or two older and has to be clean , I'm really not happy as iv spent so much money thinking I'm buying a quality sneaker that will last but yet not even two months old it's damaged And through the experience I also had with my request I'm not comfortable with the brand and the store anymore