he might be sulking or waiting for you to say you were wrong and beg him.<br />
Perhaps he is mad again.<br />
Why don't you ask him if he is mad with you?
ok, so just leave him a lovely message like
"HEllo xxx, I'm missing you and wish that you were still talking to me. I hope everything is well for you. I'm sorry I couldn't talk to you yesterday as I had a very busy afternoon. When you are ready to talk, I'm here and looking forward to it. In the meantime I'll respect you need for space.
lots of love (or whatever)"
you can't make him talk to you.
how do you know he didn't read them?