Party Up to Party Down soft lock

Hi so iv got to step 4 of 5 In party up to party down, and i need to play a session in coop, but if I telport to a player to start a session the game dosnt start the session mission, and I can skate and explore the world. But theres 0 npcs, 0 traffic 0 players. And I cant open any menu or map and UI vanished