Can't get one persons texts on iPhone 5?

So my boyfriend has an iPhone but he uses the iMessage thing. So we Both have iMessage and there has never been a problem like this. He is getting my texts but I'm not getting any of his? I have turned my phone on and off like 5 times and I still can't get them. Is there anything I can do?

Added (1). My boyfriend has an iPod* sorry

Go to setting ands turn your iMessage off for a while. Then after a few hours turn it back on. Tell him to do the same and just text you with regular text message. This happens to me all the time with my iPhone.

If he has an iPod, he won't receive messages unless he is connected to Wi-Fi