It won't go away Princess G, the reason it went before is definitely because you changed your profile. It sucks I know, but that's the way it works for some reason. I've had a day before where I got a custom avatar, then changed my profile, then got my avatar back, then realised there was something wrong on my profile, changed it and then had to go and get my avatar again
. I dunno why it does that, you might wanna ask some staff or something, but yeah, a word of warning I guess .... don't change your profile if you don't want to lose your custom avatar.