You need to get to the heart of the problem. Try opening up the laptop and blowing out any dust.
I've tried opening it before with no success. I don't know much about computers in general and it's pretty worrying if I end up messing it up.
It's a weird model, to open the whole thing you have to take the keyboard off as well which was what I got stuck at before. However I can try and get some dust out since I haven't done that in a while but I don't think it will help much.
I have cleaned everywhere I could with my small duster for the outside of my laptop and currently have around 80 degrees on my CPU and GPU after playing one game. It's helped massively and hopefully it will stay like that since I've only played a little so far.