Why do I feel like I am being lead on?

My partner basically stops answering my calls before we have plans, I tell him I am calling at a certain time and about 60 percent of the time he doesn't answer. I get tempramatic when he doesn't show he is there. He doesn't understand this that I need him to answer when I call him. I think he cares he will lose me, but doesn't realise it until I pretend like I am moving on, and it will make him very angry and revengeful, I just don't wanna deal with it even if I can. I want to communicate effectively that he's losing me by showing ignorance and carelessness.