2010 BMW 320 - Fishy smell

Hi, iv a fishy odour coming from air vents, seems to go away when I use ac then if I switch that off the smell returns worse than before. I can smell some chemical smell as engine is warmed up. Anyone had similar problems and have any advice would be greatly appreciated.
Thanks Gordon

Why not simply take this very new car back to the dealer and have them fix it under warranty?

Hi, I don’t know why car is stated as 2020 model, that wouldn’t be out yet. Its a 2010 model mate!