I Like Him So Much But He Doesn’t Seem To Care About Me?

Well we message each other online and often it takes him days to reply to me even when I see him online so I know he must notice the message. He said one time sorry and he just forgets to reply sometimes but surely he’d start paying attention after that but he didn’t. When he does reply we have good conversations though :/ he never starts the conversations though but he seems fine with answering my questions. I just don’t know if I’m wasting my time.