Refuse to Repair Couches!!!!

I purchased 2 Sierra Oxblood leather couches in December from Rochester The Grove because I want good quality couches. About 2 weeks ago I saw that the stitching is pulling loose. I phoned Rochester The Grove and they collected my couches. I phoned after a week to follow up on what is happening with my couches. They refuse to repair my couches because they cannot see where the stitching is pulling loose and because there is scuff marks also! I have never in my life spoke to such *********** people! They just don't care and don't want to listen. Their reasons is so pathetic and out of line and unreasonable!!!! I spoke to the manager and he told me that they in any case don't have the material to repair the couches. Maybe I should hold my payments back???