Damaged couch and general poor quality

I ordered a leather couch from Coricraft. On delivery I noted horrible black marks on the light grey leather. It literally looks like someone scribbled on it with a black pen. I was told that it is the natural markings but as someone who has worked in the leather quality control industry, it is clear that the leather used was exceptionally poor quality. I was promised that I will be contacted and it will be exchanged. Needless to say, this never happened. Apart from the poor quality leather used the general workmanship is shocking. I also paid for Scotch guarding that clearly was not done either. Extremely disappointed.