Why would a guy text someone saying "Hi", and then after the person replies back saying hey, he never writes back? Why? What's the purpose of texting that person if you're not gonna talk? Is this some kind of game people play or something?
and it worked. it is a game. so next time he text you again wait about 30min before replying with a short answer (just don't explain why you took too long) when he replies back don't reply again until a couple hours after. (again short answer) he'll see your not his priority and that will keep you on his mind.