Убедитесь, существует ли комната в Socket.io
if (io.sockets.adapter.rooms.has(roomIdentifier]) {
socket.join(roomIdentifier);
} else {
console.log(socket.id + 'tried to join ' + roomIdentifier + 'but the room does not exist.');
// Socket.join is not executed, hence the room not created.
};
Encouraging Eel