This guy that i was really close to about 3 years ago saw my other friend and gave his number to her to give to me I tried calling twice and left 2 messages and i havn't gotten a call back why?

There could be several reasons why he hasn't returned your calls. He might be busy or preoccupied with other aspects of his life, or he may not be ready to reconnect after the time apart. It's also possible that he didn’t receive your messages or didn't know how to respond. If you're still interested in reconnecting, consider reaching out through a different method, like a text or social media message.