Cannot see any player skins (they become steve and alex)

Hey,

I have had this problem for a little while and its becomming pretty anoying. The thing is i cannot seem to find any information about this problem so i would like some help. The problem is like it said in the title i cannot se any skins even my own skin. And i also run optifine but i cannot see my own cape (i could about a year ago but then i quit playing). Im really hoping someone could help me on this one thanks.