Santa is Real (6:39)
IMDb; YouTube

This was released in 2014, but I first saw it in 2017. Anna Akana plays a young woman named Anna, who still believes in Santa Claus. Her friends always go to great lengths to avoid spoiling her belief. But this year, a guy named Phil crashes the Christmas party of some mutual friends. He's shocked to learn that someone Anna's age still believes in Santa, and ends up telling her that Santa isn't real. And... there are a couple of plot twists after that, which I don't want to spoil. But it's a fairly amusing film.