PDO语句没有执行，没有错误

Question

我一直试图让这个单一的PDO语句工作，它只是不想执行！

我有数百个类似的语句，它们都执行得很好，但这个单一的语句无法执行。甚至没有任何错误消息要显示。要么我忽视了一些非常简单的东西，要么就是出了问题。

<?php 

require_once('inc/connect_dbo.php');

//Add dummy client
$first_name = "John";
$first_name = "Smith";
$client_type = "individual";
$individual_email = 'john.smith@email.com';
$gender = 'male';
$primary_phone = '1234567890';
$address = '1 Yonge St, Toronto, ON';

$query = $dbo->prepare("INSERT INTO clients SET account_id = ?, first_name = ?, last_name = ?, type = ?, email = ?, gender = ?, primary_phone = ?, address = ?");
$query->execute(array($account_id, $first_name, $last_name, $client_type, $individual_email, $gender, $primary_phone, $address));

$client_id = $dbo->lastInsertId();

print_r($dbo->errorInfo());
echo $client_id;
exit;

?>

errorInfo的输出是emtpy：

Array ( [0] => 00000 [1] => [2] => ) 0

提前致谢！