My Minecraft doesn't accept my skin and this only happens to me.

My Minecraft doesn't want to accept the skin I created for myself, like a warning appears saying that it has to be in .PNG, and in a 64 x 64 format, but my skin is in .PNG and in a 64 x 64 format, I asked For a friend to test the skin and in his Minecraft it was but in mine it wasn't.