Need help with Gaming laptop

So I have a laptop with a 4060 and 2 ddr5 rams so it's a good laptop problem is recently whilst playing the screen flashes black and then back to my game. I tried Ctrl+win+shift+B it didn't work. And sometimes the thing doesn't even turn on even with full charging it just doesn't turn on if I press the power button and then magically fixes it self hours later.