I know this isn't a bug but the GM's and email support have directed me here. A few days back I got tired of my Elf so I decided to use one of my fantasias. I logged out and created my character saving it ready to use with my item. Popped my Fantasia, everything was going fine with my new designed character till I logged back in and I had the default Au'ra. So I decided to use my 2nd and last Fantasia the next day, repeated the process logged back in and it changed me to my original character. Now I'm back with my original Elezen and 2 fantasias down.

If it's possible you can check back on my account which will have 2 items used in just over 12 hours