Why would he do this?

This guy I like (26M) messages me (24F) or snaps me or he will respond to things I post on my story here and there, but when I respond, he either takes a long time to respond or he doesn't try to continue the convo. I am so confused cause he is the one that reaches out, so why even bother if you're not even going to have a conversation?

Something happened between us because of a friend, so we stopped talking a couple of months ago, but then we cleared the air, and he started messaging here and there.

Why?

Thank you!