Turning my sim into a vampire resets her appearance

To put things short. I turned my sim into a vampire. She has a unique appearance. Once I turned her into a vampire. Her appearance was reset. And I had to recreate her face. I tried googling and I can't find related answers. I tried other sites but posts are getting removed.  Is this a bug? A bug related to mods? This is one of those instances where the generated sim model is really good. And I don't want to lose it