Unpaid Utilities and Missing Mail

My question involves a roommate in the State of: Oregon

I recently moved out of a home I shared with another male roommate. All of the rent is paid on the lease of which I always paid half. The last months bills have not been paid but havent been received yet either. All of the utilities (H20, electric, etc) were in his name. He moved out first and submitted a forwarding address. Before the change occured, mail was still being sent to the house. He came by to collect any mail that was not forwarded. I think he was expecting mail because he kept leaving me voice messages demanding his mail (although he never said specifically what he was expecting). Now he keeps sending me harrassing emails and phone messages demanding "mail" that I don't have, never saw, and don't even know what mail he is looking for. Also, he claims that I am refusuing to pay the last utilities but I havent seen bills and dont even know the amount. I never said I wouldnt pay... he is claiming that but I never once said it. He is now claiming that he is getting legal action (suing maybe?) for withholding mail and unpaid bills. Does he have a case? How do I get him to stop harrassing me? I saved all of the voice mails, text messages, and emails.

If you're not withholding mail, you're not withholding mail.

If you owe him money for utilities, then obviously he is entitled to that money; but he'll have to document the amount for the court.