PHP update() function not working

I am developing a web application and need to update database entries as per user requirements via forms. I am using the Savant templating engine for the MVC structure. All was going fine till I went on to test the update() function. When I filled the update form and clicked the update button, it led to a blank screen with the URL of update.php. Here's the code of the Update.php page:

<?php
    include_once("../../Resources/Libraries/Savant3.php");
    include_once("../../Classes/Models/Test.php");
    $s=new Savant3();
    $s->method=$_SERVER['REQUEST_METHOD'];
    if($_SERVER['REQUEST_METHOD']=="GET")
    {
        $b=Test::readSingle($_GET['id']);
        $s->b=$b;
        $s->display("UpdateView.tpl");
    }
    else
    {
        $b=new Test();
        $b->id= $_POST['id'];
        $b->title= $_POST['title'];
        $b->address= $_POST['address'];
        $b->location= $_POST['location'];
        if($b->validate==true)
        {
            Test::update($b);
            header('location: ../../Applications/Success');
            return;
        }
    }
?>

I think that the problem is, most probably, somewhere in the above code. In case you wish to see the update() function in the m开发者_运维技巧odel, here it is:

public static function update(Test $b)
{
    $id=$b->id;
    $title=strip_tags($b->title);
    $address=strip_tags($b->address);
    $location=strip_tags($b->location);
    $m=new mysqli("localhost", "XXXXXXXX", "XXXXXXXXXXX", "XXXXXXXXXXX");
    $s=$m->prepare("update test set title=?, post=?, location=? where id=?");
    $s->bind_param("sssi", $title, $address, $location, $id);
    $s->execute();
}

Please help in case you have any information. This is important! Thanks in advance. :)

As I specified under the comments under the question, I got my problem solved as I realized that I was missing a pair of parenthesis after the validate() function. Cheers.