Won a game, But lost a promotion? please help

So this is what happened: I started a promotion to gold 2 and the 29th august played 2 games where i won the first one and then lost the second one, so later that night i decided to go play the last promotion game and sadly just at the beginning my internet connection goes off. after some time I get to finally reconnect and miraculously my team was winning, i started playing and we did actually achieve to win that game, I got a message about my promotion which i didn't read and skipped stats. then i randomly see at my profile i actually was Gold3 89PL which meant i actually lost my promotion! I mean even if I understand most part of the game I was disconnected I did my best to reconnect and then help to win the game. If its okay it would be nice to be positioned at Gold2 0PL which would be where i would have ended if I win that promotion.

This match history shows the 3 promotion games: 1Won with poppy, 1Loss with Sion and finally 2 Win with Garen (The game where I DC).

Sincerly, Gotthard.