Karrimor Backpacks - Non Refundable

I returned my sons school bag last week. I bought it in January and 3 months later it looks like a bag that’s been used for years. Coming loose in certain places and thinning in others. I was advised that return was declined after evaluation. I am still waiting for the bag to be returned. I returned another bag I bought for my niece that didn’t even last a month and it broke. The reasons for returns they give you is limited to: damaged in transit or item defective. Both bags cost just under 800 I bought it as this used to be a quality brand.