Inserting data into database using pdo

keep failing inserting data into database... im totally newbie in this... just need someone to explain the correct way inserting data

<?php   
    //TO ADD DATA
    if (isset($_POST['add'])) {
        $conn = new PDO("mysql:host=localhost;dbname=fzdb", 'root', '');
        $stmt = $conn->prepare("INSERT INTO 'order' (phone, name, address, city, state, postcode, product, size, quantity) VALUES 
            (:Phone, :Name, :Address, :City, :State, :Postcode, :Product, :Size, :Quantity)");

        $stmt->bindParam(':Phone', $phone);
        $stmt->bindParam(':Name', $name);
        $stmt->bindParam(':Address', $address);
        $stmt->bindParam(':City', $city);
        $stmt->bindParam(':State', $state);
        $stmt->bindParam(':Postcode', $postcode);
        $stmt->bindParam(':Product', $product);
        $stmt->bindParam(':Size', $size);
        $stmt->bindParam(':Quantity', $quantity);

        $phone = 'Phone';
        $name = 'Name';
        $address = 'Address';
        $city = 'City';
        $state = 'State';
        $postcode = 'Postcode';
        $product = 'Product';
        $size = 'Size';
        $quantity = 'Quantity';


        $stmt->execute();
    }
    ?>