MMR Bug? win 17 of 20 games no double promo?

So I won 17 of my last 20 ranked games, including 16 of my last 17 ranked games, with no double promotion. almost all were duo.

Is there some bug in the mmr system, why am i not skipping a league? I was demoted 7 divisions in placement and now grinding back up.

Was scaling mmr removed where more wins in a row boosts you?

sorry a little tilted i have to play a billion games to get to master... is this to prevent qtpie from having 200 accs in challenger or something?

V