7 Day Ban For Leaving and Rejoing!

I was playing Overwatch “Competitive 6v6 Elimination” and my game crashed which was probalbly on my end, but I booted on the game and rejoined then we won. At the end of the game (I was doing placements) it said that I lost that game and when i got to the lobby, I got a 7 day ban. Blizzard please. Explain!

With Competitive 6 vs 6, there is only about 10 seconds to rejoin the match (in normal Competitive the leaver timer is 2 minutes). Rejoining too late still results in a penalty. This is not a bug but a normal function of the game.