Really want this to work but I’m unhappy

So I’ve been dating this guy for about a month now and I am very vey unhappy. I didn’t want to be in a relationship before hand but I tried to give it a shot because he seemed like he really wanted to date me and I had always liked him however I knew after the last relationship I was in I needed to be by myself. Recently we barely talk like we have good conversations and stuff but I want to face time him and make time to see him like I have always tried to do. Recently he told me he needed to talk to me so I was like oh crap okay so I wait and wait and wait and he never calls and barely text. He tells me to wait for him I do and then he doesn’t call. He won’t talk to me the next day and I’m just so confused as to why he’s doing this and why I feel like I’m trying so hard. He is older than me by 4 years but he was able to talk to me before hand so I don’t see why he has barely any time to talk to me now. I don’t know how to approach the situation without him just wanting to break up unless that’s what he wants to do, he’s not acting like he’s 23 he’s acting more like he’s 18 and not really caring and I don’t know what to do anymore? Any suggestions