missing mermaid outfit in game

I think my special outfits somehow got deleated on one of my game files. So my mermaids arnt acting like mermaids anymore. they still have the mermaid traits (scales on legs, hydration bar, blue needs bard can dive underwater without scuba suits ect) only thing is when they go into the water they switch into swim wear and not tails. they also swim like normal sims. i tried using mastercontroler to edit special outfits, but the option for special outfits isnt even there. I tried it on other game files and it everything works just fine. its just this one. can i fix it? i'v gotten far and dont wanna start over.

 also i stared a new file now there are NO mermaids. none of the base sims are mermaids, yes im in the right world