Sort dropdown search result

I have a dropdown with search function that use select2 library. what I want to do now is, I want the dropdown search result shows the result that begin with the letter that user key in, in the placeholder. My big problem is, the dropdown will shows two data which are customer_code at the front and followed by customer_name. I want the result sort by customer_name. For example, if the user type 'F' than the dropdown will shows all customer_name that start with letter F. Can someone help me how should I edit my script to achieve the result that I want?

Here is what I've don so far:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.0/jquery.min.js"></script>

<link href="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.13/css/select2.min.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.13/js/select2.min.js"></script>

<div class="CodeDropdown">
    <div class="form-group"><label>Select Customer</label>    
    <select id="ddlModel"> 
        <option value="">-- Select Customer --</option>
            <?php
                include "dbconnect.php";
                $records = mysqli_query($conn, "SELECT * From customer_list ORDER BY customer_name ASC");
                while($data = mysqli_fetch_array($records)) {
                    echo "<option value='". $data['customer_id'] ."'>" .$data['customer_code']. "      -      " . $data['customer_name']."</option>";
                }
            ?>  
    </select>
    </div>
</div>
    
<script>
    $(document).ready(function(){
         $("#ddlModel").select2({
            matcher: function(params, data) {
                // If there are no search terms, return all of the data
                if ($.trim(params.term) === '') {
                    return data;
                }
                
                // Check if the first character of the search term matches the first character of the data text
                if (data.text.charAt(0).toLowerCase() === params.term.charAt(0).toLowerCase()) {
                    return data;
                }
                
                // If it doesn't match, return null
                return null;
            }
        });
    });
</script>