PHP fails at inserting values into database - php

Question

I'm using a WordPress theme for my site, but customizing it has given me such a headache that we are trying to use our own hand written from instead of the one provided by WordPress.
I have written a php-script that should insert values from this form into a custom table in a custom database outside of the wordpress database. How ever when I try to run it I get no error messages, and no data is inserted into the database.
my PHP code, please not that I have changed the $user and $pass to not show here. I've tested the login info used in this script via terminal on my database, and it worked fine. See the full file here page.sign.php
if(isset($_POST['submit'])) {
$lastname = $_POST["lname"];
$firstname = $_POST["fname"];
$email = $_POST["email"];
$affiliation = $_POST["affiliation"];
$country = $_POST["X"];
$position = $_POST["position"];
$hindex = $_POST["scholar"];
$gender = $_POST["optionsRadios"];
$city = $_POST["city"];
$webpage = $_POST["webpage"];
$newsletter = $_POST["newsletter"];
//Source https://gist.github.com/adrian-enspired/385c6830ba2932bc36a2
$host = "localhost";
$dbname = "petition";
$user = "<username>";
$pass = "<password>";
$charset = "UTF8MB4"; // if your db does not use CHARSET=UTF8MB4, you should probably be fixing that
$dsn = "mysql:host={$host};dbname={$dbname};charset={$charset}";
$options = [
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_EMULATE_PREPARES => false
];
try {
$pdo = new PDO($dsn, $user, $pass, $options);
} catch (PDOException $e) {
echo "<h1>Error connecting to the database </h1>";
}
$stmt = $pdo->prepare("INSERT INTO petitioners (lastname, firstname, email, affiliation, country, position, hindex, gender, city, webpage, newsletter)
VALUES
(:lastname, :firstname, :email, :affiliation, :country, :position, :hindex, :gender, :city, :webpage, :newsletter)");
$stmt->bindParam(':lastname', $lastname);
$stmt->bindParam(':firstname', $firsname);
$stmt->bindParam(':email',$email);
$stmt->bindParam(':affliation',$affiliation);
$stmt->bindParam(':country',$country);
$stmt->bindParam(':position',$position);
$stmt->bindParam(':hindex',$hindex);
$stmt->bindParam(':gender',$gender);
$stmt->bindParam(':city',$city);
$stmt->bindParam(':webpage',$webpage);
$stmt->bindParam(':newsletter',$newsletter);
$stmt->execute();
echo "<h1>Signatory succefully registered</h1>";
$stmt->close();
$conn->close();
}