Advice is needed

I am beyond confused. When I spend time with this guy we get on so well and flirt and kiss and everything but over message he's blunt and doesn't send kisses and we dont really talk much. I know some people might say that it could just be him and that he doesn't really go on his phone but I know that when he likes someone he'll message them and be very kind. Like how he was at the start. I've tried asking him and he just denies that he's being off with me. What can I do to try and get him back to the normal interested person he was at the start ?