unfail loss of lp

i know how the system works that you lose more lp is you were favored to win and gain more if you were favored to lose. however, when you have an afk on your team the whole game you should not lose lp as if it was a normal 5v5. what the hell i had 20lp and lost it all when i had an afk.

riot why is your system have no afk detection.

im no saying i should no have lost any lp, but i should not lose so much. feels rubbish. and now i might be demoted