Call a user again if he/she did not answer using Twilio - php

Question

EDIT: working now, editted this post to the working script.
I'm setting up an alarm which calls the user if a sensor reaches a certain value. I've got the calling part working but I need Twilio to call the user again if the user did not pick up the phone.
Currently, Twilio calls the user telling him that the alarm is going. If the user does not pick up in 15 seconds Twilio will end the call so it doesn't go to voicemail. Now the status of the call will be 'No Answer' in the Twilio console. I've tried the following code:
In my call.php:
<?php
require __DIR__ . '/vendor/autoload.php';
use Twilio\Rest\Client;
// /include 'insertcall.php';
// Your Account SID and Auth Token from twilio.com/console
$account_sid = 'xxx';
$auth_token = 'xxx';
// In production, these should be environment variables. E.g.:
// $auth_token = $_ENV["TWILIO_ACCOUNT_SID"]
// A Twilio number you own with Voice capabilities
$twilio_number = "[phone]";
// Where to make a voice call (your cell phone?)
$time = time();
$call_id = $sensor_id . $time;
echo "callid: ";
echo $call_id;
echo "<br><br>";
$client = new Client($account_sid, $auth_token);
$client->account->calls->create(
$callto,
$twilio_number,
array(
"machineDetection" => "DetectMessageEnd",
"url" => "https://link.nl/includes/alarmbot/includes/cas_xml.inc.php?sensor=$sensor_id",
"statusCallbackMethod" => "POST",
"statusCallback" => "https://link.nl/includes/alarmbot/callback.php?sensor=$sensor_id&callid=$call_id",
"statusCallbackEvent" => array(
"completed"
),
"timeout" => 15 // Wanneer niemand op neemt na 15 sec -> No Answer zodat we niet naar voicemail gaan en alsnog als completed gaat.
)
);
$conn = mysqli_connect($servername, $username, $password, $dbname);
$sql5 = "INSERT INTO twilio_calls (id, sensor_id, completed) VALUES ($call_id, '$sensor_id', '0')";
if ($conn->query($sql5) === TRUE) {
echo "New record created successfully";
} else {
echo "Error: " . $sql5 . "<br>" . $conn->error;
}
In my callback.php:
<?php
ini_set('display_errors', 1);
error_reporting(E_ALL);
setlocale(LC_ALL, 'nl_NL');
require 'includes/boot.php';
use Twilio\Rest\Client;
$servername = "localhost";
$username = "xxx";
$password = "xxx";
$dbname = 'xxx';
$account_sid = 'xxx';
$auth_token = 'xxx';
if (isset($_REQUEST['CallStatus'])) {
$call_status = $_REQUEST['CallStatus'];
$call_id = $_REQUEST['callid'];
$twilio_number = "+mynumber";
echo $call_status;
echo "<br>";
echo $call_id;
echo "<br>";
if ($call_status !== 'completed' && $call_status !== 'busy') {
$conn = mysqli_connect($servername, $username, $password, $dbname);
$sql = "SELECT * FROM twilio_calls WHERE id='$call_id'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
while ($row = $result->fetch_assoc()) {
$sensor_id = $row['sensor_id'];
$sql_2 = "SELECT telefoonnummer FROM alarmnummers WHERE sensor_id='$sensor_id' AND backup = 1";
$result_2 = $conn->query($sql_2);
if ($result_2->num_rows > 0) {
while ($row_2 = $result_2->fetch_assoc()) {
$telefoonnummer = $row_2['telefoonnummer'];
echo $telefoonnummer;
$client = new Client($account_sid, $auth_token);
$client->account->calls->create(
$telefoonnummer,
$twilio_number,
array(
"url" => "https://link.nl/includes/alarmbot/includes/callback.php?sensor=$sensor_id",
"timeout" => 15
)
);
}
} else {
echo "query ni goed";
}
$sql_3 = "UPDATE twilio_calls SET completed=1 WHERE id='$call_id'";
$conn->query($sql_3);
}
} else {
echo "andere query ni goed";
}
} else {
$sql = "UPDATE twilio_calls SET completed=1 WHERE id='$call_id'";
$conn->query($sql);
echo "Updated, call busy or completed";
}
} else {
echo 'No valid callback';
}
So I need to call the user again when he/she did not pick up. I am not really sure how I am supposed to do this.