it crashed by me opening an app in my laptop and crashed it
also sometimes the game launcher loses connection for no reason and you cant join a game so you lose sr
Leaving games will result in penalties, regardless of the reason, because it puts your team at a disadvantage. Even when the game closes due to leavers, everyone’s time has been wasted in the queue for the match. SR is never refunded for any reason. You can read more about Blizzard’s stance on leavers and their penalties in this sticky at the top of the forum.
It sounds as though your internet connection is not stable enough to play high-stakes modes (Comp). I recommend investigating your connection quality and avoiding any modes which will cause SR loss.