php bind_param Forbidden

Question

I need to do the insert of the contents made in the editor summernote.

Only that the bind_param is blocking because the editor generates html content. Example:

<p style="text-align: center; "><b>Titulo</b></p>

Then when I do Submit, this message appears:

Error: Forbidden: You don’t have permission to access /file.php.

How to allow the bind_param allow insertion?

My code:

if ((isset($_POST["form"])) && ($_POST['form'] == "form1")) {
  $rs = $mysqli->prepare("INSERT INTO contratos (nomeContrato, texto, dataModificado) VALUES (?, ?, ?) ");

  $rs->bind_param('sss',
    $_POST['nomeContrato'],
    $_POST['texto'],
    $_POST['dataModificado']
    );

  $rs->execute();


  if ($rs->errno) {
    echo 'Erro: ', $rs->error;
  } else {
    echo "<script>window.location='sucesso.php'</script>";
  }
}