Cannot retrieve order_id from database with SQL query

Question

We are trying to update WC orders based on an external script.

However, the script is unable to acquire the order_id for some reason. I tried to run the SQL query manually within the database and it returns the order ID without issue.

I am pretty sure that I am querying the database properly, but I cannot seem to figure out what part is wrong.

Tried with $order=wc_get_order($order_id) with no luck.

Here is the code:

<?php

/*

  
*/

/*

*/
define("ConfirmKeyword",   "CF ETIN");
define("CancelKeyword",    "AN ETIN");

/*
    Enable/Disable Debug Output - Make Sure is Disabled (set to false) in Production
*/
define("EnableDebugOutput", enable);

if ((isset($_GET["sender"])) and 
    (isset($_GET["receiver"])) and 
    (isset($_GET["message"])) and 
    (isset($_GET["timestamp"])) and 
    (isset($_GET["network_id"])) and 
    (isset($_GET["network_name"]))
  )
{
    /*
        Load WordPress
    */
 define( 'WP_USE_THEMES', false );
 require_once( $_SERVER[ 'DOCUMENT_ROOT' ] . '/wp-load.php' );     
    /*
        The Sender of the SMS (ie. 07xyzzzzzz)
    */
    $sender = $_GET["sender"];  
    
    /*
        The Shortcode on which the SMS was sent (ie. 17xy, 18xy, 37xy, 38xy etc.)
    */
    $receiver = $_GET["receiver"];
    
    /*
        The Message sent by the Sender to the Shortcode
    */
    $message = $_GET["message"];
    
    /*
        The Timestamp in which the Message was received on the Shortcode, in UNIX Timestamp format.
    */
    $timestamp = $_GET["timestamp"]; 
    
    /*
        The Network ID in which the Sender is located
    */
    $network_id = $_GET["network_id"]; 

    $network_name = $_GET["network_name"]; 
    
    $sql_query = $wpdb->prepare(
                        'SELECT post_id 
                           FROM wpdq_postmeta
                          WHERE ((meta_key = "_billing_phone") OR 
                                 (meta_key = "_shipping_phone")
                                ) AND 
                                ((meta_value = %s) OR 
                                 (meta_value = %s) OR
                                 (meta_value = %s) OR
                                 (meta_value = %s) OR
                                 (meta_value = %s) 
                                )
                       ORDER BY post_id DESC
                          LIMIT 1
                        ',
                        $sender,             // Search for    07xyzzzzzz
                        substr($sender, 1),  // Search for     7xyzzzzzz
                        "4".$sender,         // Search for   407xyzzzzzz
                        "004".$sender,       // Search for 00407xyzzzzzz
                        "+4".$sender         // Search for  +407xyzzzzzz
                    );
    
    
    if (EnableDebugOutput == true)
        echo "Debug: SQL Query: ".$sql_query."<br />";
    
    $entry_id = $wpdb->get_results($sql_query);
   
    $order_id = $entry_id[0]->post_id;

    if (EnableDebugOutput == true)
        echo "Debug: Found Order ID: ".$order_id."<br />";
    
    /*
        Load Order Data
    */
   if (!is_null($order_id))
    {
        if ($order_id > 0)
        {
            $order = new WC_Order($order_id);

            /*
             * 
             * 
             * Client Confirms Order by SMS
             * 
             * 
             *                 
            */
            if (strtoupper(substr(trim(urldecode($message)), 0, strlen(ConfirmKeyword))) == strtoupper(ConfirmKeyword))
            {
                if (EnableDebugOutput == true)
                    echo "Debug: Order Confirmed<br />";
                
                /*
                    Update Order Status as you wish
                */
                $order->update_status('on-hold');
                
                /*
                    Create an Order Note
                */
                $note = __("Confirmed by".$sender." la ".$receiver." on ".date("d-m-Y H:i:s", $timestamp)." from ".urldecode($network_name)." text: '".urldecode($message)."'");
                
                /*
                    Add the Order Note
                */
                $order->add_order_note($note);
            }
            
            /*
             * 
             * 
             *  Client Cancels Order by SMS
             * 
             * 
             *                 
            */
            if (strtoupper(substr(trim(urldecode($message)), 0, strlen(CancelKeyword))) == strtoupper(CancelKeyword))
            {   
                if (EnableDebugOutput == true)
                    echo "Debug: Order Canceled<br />";
                
                /*
                    Update Order Status as you wish
                */
                $order->update_status('cancelled');
                
                /*
                    Create an Order Note
                */
                $note = __("Cancelled by".$sender." la ".$receiver." in ".date("d-m-Y H:i:s", $timestamp)." from newtork CODE".urldecode($network_name)." with the message: '".urldecode($message)."'");
                
                /*
                    Add the Order Note
                */
                $order->add_order_note($note);
            }            
        }  
        else
        {
            if (EnableDebugOutput == true)
                echo "Debug: Order Not Found<br />";
        }      
    }
    else
    {
        if (EnableDebugOutput == true)
            echo "Debug: Order Not Found<br />";
    }
    
    echo "Message Successfuly Received.";
}
else
{
    echo "Invalid Request.";  
}
    ?>