iPad automatically reset and cannot be updated in to 9.3.4

I have an iPad Air 2 which I bought a few months ago. However, now, my iPad are having a big errors and it makes me feel angry. When I am using them, the iPad automatically turned off without doing anything. It means that my iPad automatically reset and sometimes, it automatically do that for hours. Moreover, rightnow, I cannot update into 9.3.4. The reason is that when I plugged in my Macbook, the Itunes cannot loaded and it makes my Macbook stuck, so that I need to reset my Macbook again. My iPad used to have this error before but now, it is facing with it once again. A month ago, my iPad had the same problem. But then, it's normal until now, so that I need to ask for help right now. My iPad is iPad Air 2 64GB Wifi ( MH0W2LL/A). I hope you guys can help me, because I have so many game progress in their and if I restore, all my progress will be lost. Thank all of you really much. I cannot find anyway to fix it right now

Hope and waiting for your reply

Lucas