If it doesn't resolve please let me know. I might be able to help you. I remember having a similar issue for a little bit. I'm not a moderator or the creator just a fellow streamer and player of the game.
Have you downloaded and installed the DLC already, as the other moderator suggested? If so, please visit the DLC's Itch page and I can try to help further. This comment section is mainly for the base game.
