Error with TableSorter - JQuery

I'm wanting to order, but when I click on the headers, this happens.

When I do it with a table created in hard (hard data) it works perfectly, also when the data is already loaded from the beginning with PHP, but when I fill the table from the comboBox, that happens.

HTML

<table class="datos" id="myTable">
            <thead>
            <tr>
                th con los cabezales
            </tr>
            </thead>
            <tbody id="tabla">
            </tbody>
        </table>

PHP to fill table (in this same way I fill the table without needing the comboBox and it works)

<?php
require_once 'conexion.php';

if (isset($_POST["selected"])){
    $ubigeo = $_POST["selected"];
    $consulta = Query;

    $queryResult = $pdo->query($consulta);

    $html = "";
    $string = '.';
    while ($row = $queryResult->fetch(PDO::FETCH_ASSOC))
    {
        $html .=
            '<tr class="fila">'.
            '<td>'.
            td con las filas
            '</tr>';
    }

    echo $html;
}else{
}
?>

JS to fill the table with the comboBox

$(document).ready(function(){
    $("#provincia").on('change', function () {
        $("#provincia option:selected").each(function () {
            elegido="9";
            $.post("datos/tablaCandidatos.php", { elegido: elegido }, function(data){
                $("#tabla").html(data);
            });
        });
    });
});