Longtime fans of The Hunger Games may spot an elephant in the room in The Hunger Games: The Ballad of Songbirds & Snakes. District 13, the instigator of the uprising against the Capitol in the future nation of Panem, never so much as crosses the lips of any character onscreen. That's well in keeping with the franchise's history as the District was supposedly destroyed during the uprising and stricken from the Panem records. Their return to lead a second uprising at the end of The Hunger Games: Catching Fire is one of the saga's big twists, but 65 years earlier in Songbird & Snakes, they have effectively ceased to exist. At least as far as Panem is concerned.
Source：https://www.cbr.com/the-hunger-games-songbirds-snakes-district-13/
