infinite scroll network 200 but undefined

//API
export const getMessageList = async ({roomId, pageNum}: {roomId: string, pageNum: number}) => {
    console.log("roomId", roomId, "pageNum", pageNum);
    const token: string | undefined = Cookies.get("access_Token")
    const res: Response = await instance.get(`${process.env.NEXT_PUBLIC_API_URL}/chat/${roomId}?page=${pageNum}`, {
        headers: {
            'Authorization': `${token}`,
        },
    });
    if (!res.ok) {
        throw new Error('Failed to fetch data');
    }
    return res.json();
};

//Component
export default function Message({messages, roomId}:{messages: ContentType, roomId: string}) {

    const {
        data,
        fetchNextPage,
        hasNextPage,
        isFetching,
    } = useInfiniteQuery<any, any, [string, string, string], any>({
        queryKey: ['chat', 'messages', roomId],
        queryFn: ({ pageParam = 0 }) => getMessageList({ roomId, pageNum: pageParam }),
        initialPageParam: 0,
        getNextPageParam: (lastPage: any) => (lastPage.data?.length > 0 ? lastPage.page + 1 : undefined),
        staleTime: 60 * 1000,
        gcTime: 300 * 1000,
    });


    console.log(data)

    const {ref, inView} = useInView({
        threshold: 0,
        delay: 0,
    });

    useEffect(() => {
        if (inView) {
            !isFetching && hasNextPage && fetchNextPage();
        }
    }, [inView, isFetching, hasNextPage, fetchNextPage]);

    return (
...