Problem with Elo, mmr, and match making

ok this is my account. im currently placed iron1. For the placement, out of 8 games, i won 6 and lost2. during the placement, my solo Q mmr was plat5-gold1. And after i finish the placement, all of sudden my mmr drops to Iron2 and i get placed in iron4. I get that the new system where new players get placed in iron elo nomather what. But my question is, my mmr got reset to Iron. HOW in the world am i keep getting matchmaked with plat5- high gold players. Someone explain wtf is going on. For all my games ever since i finished my placement games(during placement games i was playing with plat-gold palyers too), I am literally the only iron elo and mmr player in the entire team including enemy. Riot, please answer me.