Missions bug:Unbeatable 350 farm?

ive had the "win 5 games where your team farmed 350 minions" mission for a few days already, and i was only able to get two, then, for some reason, it stopped working. i realized this when, after a lot of games, i hadn't advanced at all. i checked my match history, the farm of my team, and realized that i should have already completed the mission, since most of them met the requirement. Its one day away and i cant get to do the mission because it bugged? seems wrong. please fix