My bf(21m) never calls me (20f)

He never calls me but we text a lot like a lot. We’re doing a long distance relationship and time difference is like 8h. He never called me on my birthday and also on Valentine’s Day. When we meet every 6months everything is perfect and we have nothing to fight about but whenever we’re back to long distance this calling problem always appears to be a problem. I talked about him on Valentine’s Day that why didn’t he call me even though I asked him to. I been telling him to make time for Valentine’s Day so we can call. He said yes but didn’t call me. And he keeps saying just sorry and he’s busy with work and school. I fucking hate him but love him. Is it time to leave ? Our 1 year anniversary is coming in 1 week and all I’m worrying about is whether he will call me or not.