[CLIENT] Lost promote after 1W/1L

Hi summoners,

So i recently got into promote to Silver 1 the August 21th. Then i left for 5 day. When i came back, i check up on the Leagues windows on the profile, and i was still in series. So i start 2 game : The first one i lost 5/6/10 and the second i win 6/2/18. ( http://puu.sh/qPkmJ/c5f32e13ee.jpg)

After that, i got check on my League tabs for some stats, then i notice that i'm not in my promote. If i remember well.. i need 2 losts to leave the promote.

So i would like to know WHY i lost it, and i would like to get my promote back with the same set ( 1W/1L). I also remember that it was the 4th time that i try to get silver 1. So i had a free win. So i NEED to be Silver 1 then...

How to recreate it... I Dunno, it happen like this right after the win 6/2/18

Thanks to notice this bug. Symh/Yum3Ni