why does tiktok make me download/save everything i post on my story? how can i stop this

so every time i post on my story tiktok makes it go to my camera roll which i do not want. idk why but when i post an actual post it doesn’t save it and only when i post on my story. i’ve tried everything i can think of and i don’t know what to do. it’s getting really annoying having to delete it out of my camera roll every time.