BAN PREVENTION FOR TEAM

I'm in low elo and I'm constantly having the problem of people not getting their wanted roles and end up trolling because of it. By this I mean they ban the champ you want to play. I really hope you can incorporate a system where you can lock one champion that your team cannot ban. I'm trying so hard to climb out of elo hell, but trolls keep banning my picks and i can't do anything but dodge and end up waiting 30 mins after every dodge. Like seriously, it is getting very annoying it literally happens 1 out of every 4 queues. I'm sick and tired of it and I hope riot takes this into consideration since im pretty sure I'm not the only one dealing with this type of poop.