skins won't show up in phone

ok guys so i was uploading some walkman skins into my w350i, i had uploaded like 5 already and they work succeful but another time i upload some other skin but any of the skin doesn't work i deleted all of them leaving only the two originals, and not even like that it wants to work, when i go to settings in my phone it only shows the option to off in skins everything else works perfect except the walkman skins... please any suggestions will be appreciated, my gues is that maybe i try to to upload some visualization and i had copy a same folder
please i need help
sorry for my bad english