无法使用PHP mysqli_stmt_fetch回显数据库中的数据

Question

What i want to do is to check if the email & username are already inside on my database, then if it is already inside the database then i want to echo out the username, how to fix this? thanks

 $sql = "SELECT * FROM user WHERE uidUser=? OR emailUser=?";
    $stmt = mysqli_stmt_init($conn);
        if (!mysqli_stmt_prepare($stmt, $sql)) {
            header("Location: ../signup.php?error=sqlerror");
            exit();
                }
                else {
                    mysqli_stmt_bind_param($stmt, "ss", $username, $email);
                    mysqli_stmt_execute($stmt);
                    mysqli_stmt_store_result($stmt);
                    $resultCheck = mysqli_stmt_num_rows($stmt);



        if ($resultCheck > 0) {
                            while ($row=mysqli_stmt_fetch($stmt)) {
                                echo "Name: ".$row['uidUser'];
                            }                   
                        }

    }