Even in business class I had some showdown with guy behind me who's angry he doesn't have more leg room. Early morning flight, I upgraded because I needed to sl

Even in business class I had some showdown with guy behind me who's angry he doesn't have more leg room. Early morning flight, I upgraded because I needed to sleep, and the guy wakes me up mid flight by violently kicking the back of my seat. When I turn to confront him he angrily tells me to pull my seat up. I don't even talk to him, I just buzz the flight attendant and told her what happened. She speaks to him but he started doing it again. I buzzed her again. Don't know what she said but this time he stopped.