Stuck in bronze 5 despite having ~60% winrate with high stat

I won 7 games and lost 4 in ranked, I somehow ended up getting the lowest rank possible at bronze 5. I read that it was patched and so I grinded ranked again, won 7 more games and did not rank up at all even after the “boost” that was implemented. A friend of mine with a winrate lower than 50% got put into silver 2 after 7 wins, and I am unable to play with him now. My stats in games are either the highest healing in the match or top 2 at least, rarely get 3rd best healing and I don’t think I ever got lowest healing. Is there a way to reset my rank and get placement matches back?