Dynamic Dropdown via PHP and Ajax

Question

Hey im trying to create a dynamic dropdown list using PHP and AJAX. Its worth mentioning that im using visual composer on my wordpress site. So i have to make it a shortcode for visual composer.

Here is currently what ive got.

    function dropdownmenu() { 
include_once "connection.php";
?>
    <div class="make">
    <label>Make</label>
        <select name="makelist" onchange="getId(this.value);">
            <option value="">Select Make</option>

        <?php       
        $query = "select distinct(Make) from websitemasterlist order by Make ASC";
        $results = mysqli_query($conn, $query);

        foreach($results as $info) {
        ?>
            <option value="<?php echo $info[Make]; ?>"><?php echo $info[Make]; ?></option>

        <?php
        }
        ?>
        </select>
    </div>

    <div class="model">
    <label>Model</label>
        <select name="model" id="modellist">
            <option value="">Select Model</option>
        </select>
    </div>

    <script src="code.jquery.com/jquery-3.2.1.min.js"></script>
    <script>
        function getId(val){
            $.ajax({
                type: "POST",
                url: "getdata.php",
                data: "make="+val,
                success: function(data){
                    $("#modellist").html(data);
                }
            });
        }
    </script>
<?php
}
add_shortcode('dropdownform','dropdownmenu');

?>

I think the error is somewhere in the ajax. because my ajax is weak.

here is the code for the secondary dynamic dropdown

<?php
include_once "connection.php";

if (!empty($_POST["make"])) {
    $make = $_POST["make"];
    echo $make;
    $query = "SELECT distinct(Model) FROM websitemasterlist where Make=$make";
    $results = mysqli_query($conn, $query);

    foreach ($results as info2){
    ?>
    <option value="<?php echo info2["Model"]; ?>"><?php echo info2["Model"]; ?></option>
    <?php
    }
}
?>

The first dropdown works. but the second dropdown doesn't show any choices when i make a choice on the first dropdown. Any help would be appreciated thank you. Its also worth mentioning that when i try to echo the make .... i dont see the make. so im pretty sure the ajax portion is messed up.

The errors I'm getting from the console