The phrase "untrue stories" refers to narratives or accounts that are not factual or based on real events. It suggests that the stories are fictional or made up. Full definition
She is telling the children untrue stories about me and not informing me of school functions that the children want me at, then she tells the children and other people that I don't care about the kids and won't come to their programs and activities. (mensrights.com)
That amounts to about 490 million untrue stories in 2017. (fortune.com)
The story that the writers for HBO's The Newsroom had been fired, first reported on The Daily, was soon refuted by Aaron Sorkin facing the TV critics Association: «A couple of weeks ago an unsourced and untrue story appeared in the... (awardsdaily.com)