Manufacturing error- black piping in white couch

My husband ordered a U shaped sofa from them. After its first professional cleaning back dye came through along the edges of the sofa by the piping. I opened up the piping area and saw that the company had inserted black non-colourfast lining into the sofa. I spoke the company and asked them to correct this as it makes no sense to put in black lining in a white sofa, they refused to help me and dismissed me, they want to charge me almost 9k to fix it, when this sofa is brand new we bought it last year. This violates my rights according to the Consumer Protection act and is a manufacturing error which the company should fix.