Why does my PHP script fail to insert html form data into my mysql database

Question

I'm trying to insert a html form into a database trough php. but when I enter the form nothing happens. im working locally in a XAMPP enviroment.

Relevant HTML code:

<form action="bestellingCreate.php" method="POST">
      Tafelnummer<input name="tafel" type="text" class="form-control">
      Reserveringsnummer<input name="reserveringID" type="number" class="form-control">
      MenuItemID<input name="menuItemID" type="number" class="form-control">
      Aantal<input name="aantal" type="number" class="form-control">
      Prijs <input name="prijs" type="number" class="form-control">
      <br>
      <input type="submit">
      </form>

I've tested the db connection, so thats not the issue. my other CRUD functions work perfectly fine with the dbCon.php. I'm also not getting any error messages, also not when i disable the header function

PHP Code

<?php
include 'dbCon.php';

if(isset($_POST['submit'])){
  $tafel          = $_POST['tafel'];
  $reserveringID  = $_POST['reserveringID'];
  $menuItemID     = $_POST['menuItemID'];
  $aantal         = $_POST['aantal'];
  $prijs          = $_POST['prijs'];

  $sql="insert into `bestelling` (tafel,reserveringID,menuItemID,aantal,prijs) values ('$tafel','$reserveringID','$menuItemID','$aantal','$prijs')";

  $result=mysqli_query($con,$sql);
  if($result){
    echo "Bestelling toegevoegd";
  } else{
    die(mysqli_error($con));
    echo"Bestelling niet toegevoegd";
  } 
}
header("Location: bestellingRead.php");
exit;
?>

image of my db table that the Create function should insert the form data into

I would love some help with this. It is for my exam in the morning and i know there is probaly some ; that ive missed or something dumb like that.