Problème boolean

<?php
session_start();
include '../../sql.php';
if (!empty($_GET['list'])) {
$iduser = $_SESSION['id'];
echo $iduser;
      //$reponse1 = $bdd->query("SELECT * FROM ".DB_prefix."matiere WHERE iduser = $iduser");
      // On affiche chaque entrée une à une
      $requser = $bdd->query("SELECT * FROM matiere");
      var_dump($requser);
      echo "ok";
      /*var_dump($reponse1);
      while ($donnees1 = $reponse1->fetch())
      {
        ?><tr>
            <td><?= $donnees1[0] ?> <button type="button" id="<?= $donnees1['id'] ?>" class="btn btn-danger btn-sm" id="supr-matieres" onclick="supprmatiere(<?= $donnees1['id'] ?>);" >suppr</button></td>
            <td><?= $donnees1['matiere'] ?></td> 
          </tr><?php
      }
      $reponse1->closeCursor(); */// Termine le traitement de la requête
      ?>
      <tr>
        <td></td>
        <td><a class="btn btn-success fas fa-plus" data-toggle="modal" data-target="#ajout" href="" role="button"></a></td>
      </tr> <?php
}