Placements season 6

Ok I'll start by saying this is my first actual competitive season but I actually finished a series of placements a day before the new season started and I was delighted to see a big silver badge pop up on my screen saying I made it into S4! Now I ask you to imagine my dismay when I finished my new placements and was put in BRONZE 4. I suppose I just want some explanation for why or how I could've fallen an entire division especially sense I have been playing with silver players for quite a while now. Thank you for any help that can be offered.