Error displaying createAt Date in NextJs from Mongo

Question

When i try to log whole mongo table it logs everything in it, but when i separatly try to log user.createdAt it logs undefined When i use user.createdAt.toString() it shows error (toString for undefined)

When using Date(user.createdAt) works fine but the new problem is I have 6 user details Only 1 of it has createAt field and its value date. But it logs 6 times and same date for 6 users, but actually the other user doesn't even have the createdAt field. I am using nextjs project and array map to render it in a table of users

const users = await fetchUsers();

console.log(users);

{users.map(user => (

    <tr key={user.id}>

        <td>

            <div className={styles.user}>

                <Image src={user.img || "/noavatar.png"} alt="userAvatar" width={40} height={40} className={styles.userImage} />

                {user.username}

            </div>

        </td>

        <td>{user.email}</td>

        <td>{user.createdAt?.toString().slice(4,16)}</td>

        <td>{user.isAdmin ? "Admin" : "Client"}</td>

        <td>{user.isActive ? "Active" : "Passive"}</td>

        <td>

            <div className={styles.buttons}>

                <Link href={`/dashboard/users/${user.id}`}>

                    <button className={`${styles.button} ${styles.view}`} >VIEW</button>

                </Link>

                <Link href="/">

                    <button className={`${styles.button} ${styles.delete}`} >DELETE</button>

                </Link>

            </div>

        </td>

    </tr>

))}

I tried logging with conditions but it like somekind of undefined data