Leaving penalty ranked

Dear Blizzard!
I´ve been playing ranked today and after 1 game I noticed that my rank dropped even though I had 400+ points in it. I didn´t know what happened but after that I noticed that I started getting penalty redemption 50P after games. I checked it out on the internet and supposedly what happened is that I got a 600 point penalty after leaving a game. But the problem is there I properly finished all of my games today so there should be no reason for me to get the penalty. Am I getting it because one of my teammates left? Please help me if you can or at least tell me the reason so I can avoid it in the future.

May b there was an issue and you got disconnected in the last few seconds, and the system registered your game as a leaver game. That is the reason.

But do not worry, thise 600 points lost are reimbursed in installments… So after a few wins, you will be where you should be (even if the leaver penalty was not given to u)