Please remove auto fill from ranked

It is not that much of a big deal in normals. After all this where you practice roles. But in ranked, when you lock in two roles that you want, then why do we get the roles that we didn't want. I was one win, ONE WIN, away from promotion., when I was hit with this Bot:- oh I got auto filled Mid:- I'll bot Me (support):- wait, you can ADC right ? Bot (previously mid):- _(after locking in)_not really Me:- oh cmon, this is my promos Bot: :)

Needless to say we lost and now I need to win two more in a row to get promoted