Why would he be using my address when he does not live here?

My neighbour applied for Unemployment Insurance about 6 months ago when his severance package finished from his job that he got fired from and now the letters are coming from the UI office to my address stating they are goin gto make a decision about his qualifications in a few weeks. I called the neighbour and told him that mail was coming to my home for him and why was he doing that. He informed me that since we had a relationship and I had insisted he live in my home , he filed the papers indicating that , eventhough , we do not live together. He was hinting that we would in the future. He has a wife and child and I am friendly with them. He takes care of his child , while the wife works 4 days a week. I am told that I could get into trouble for receiving the UI letters under false pretense. I am going to return the letters to the office and mark it ""return to sender""" . My neighbour says he will get UI cards on the Internet and post them to his bank account anyways.