only one file skin in the dressing room

in the dressing room I can only have one customized skin and if I try to put 2 different files in 2 different slots it puts the same skin in the other one too

update: I have 2 slots in the dressing room I want to put 2 different skins from my computer in png, I put the first in one of the 2 when I put the second on the other the first becomes the same skin as the second slot