Click on one of your already purchased customization. This will refresh your character and your old models will be back!
If you're afraid this might happen again in the future, create a preset (right hand side of the screen) for convenience sake, or just repeat the things i've mentioned above.
This temporary fix has worked fine for me so far. Keep in mind that i am not a dev/community manager. If this solution does not work for you, i am sorry to say that i cant help you very much.