My friend borrowed money for five years, but he didn't answer the phone or return the message. What should I do?

At least not answering the phone is to avoid you. There are only two possibilities. First, if you lose money in business or gambling, you can't afford to lose it. Second, you don't want to pay back the money. It's been a long time. Do you know his recent situation? What is the specific situation? You should go to his home or nearby to inquire before making a decision, whether to take legal channels or how to do it. I don't think you can be friends. If you are a friend, you should not answer the phone. You have to have evidence to go through legal channels, but you cheated, you have no money, and there is no good way.