I currently have as the Hair layer a customized Delish Limited Edition Magus Potion even though I never had this item, ever. So if I never had it, I never redeemed it. It's not available in the Hair section of the Wardrobe so I can't customize it again, unlike another style which I actually redeemed. I haven't tried to change this but I first wanted to report it since, well, I guess it's not supposed to be happening.

Also, since the wardrobe isn't updating with new outfits, I guess it won't probably show up to you but this is how it shows up for me.

I changed my hair to Bald, and it doesn't appear in the available hairs I have. I don't know but for now it is gone.