What should I do?

66signet, sorry to here this , I under stand you want to deal with this guy in private first, but as a seller myself after a couple weeks it's obvious he doesn't want to make it right. Communication is the key to setteling up the matter. If he doesn't want to talk and make things right with you , then you have to do what you feel is right to protect yourself and others here. This , just throwing out and not naming names makes the good stand up sellers look questionable!