Elo Bronze 5 bug

I play support and often I am top healer in the map, staying with the pack and the points, healing around 10k/10 min on moira/lucio doing all the right things, just not well enough?

So i havent played in years so I have nothing for it to go off of really, maybe this is why I will be in bronze 5 for a long time until it has enough data to climb me?

Help me out here what am I not understanding, or is 10k per 10 min the worst healing ever and that is why I am in bronze, I have nothing to base anything off of, it is rather annoying.