I recently purchase a pair of curtains described as "luxury readymade curtains" once we had hung them it became apparent that far from luxury they were poorly put together with the joins being mismatched and once hung they sagged and looked nothing like the picture on the packaging so we returned them to Dunelms but they refused a refund as we had hung them but we couldnt have seen the defects until they were hung. what can we do to get our £120 back