Stažení pdf souboru s chybou

while($row = $proved_pdf -> fetch_assoc())
         {
         echo ("<form method=\"post\">
                   <tr>
                    <td>". $row['jmeno'] ."</td>
                    <td><input name=\"nazev\" type=\"hidden\" value=\"". $row['nazev'] ."\">". $row['nazev'] ."</td>
                    <td><input name=\"cesta\" type=\"hidden\" value=\"". $row['cesta'] ."\"><a target='_blank' href=". $row['cesta'] .">Zobraz</a></td>
                    <td><button type=\"submit\"  name=\"stazeni_zip\"><a href=". $row['cesta'] .">Stáhni</a></button></td>
                    <td><button type=\"submit\"  name=\"smazanicko_zip\"><img src=\"css/obrazky/x.png\" style=\"width:25px;height:25px\"></button></td>
                  </tr>
                 </form>");
         }

if(isset($_POST['stazeni_pdf']))
    {
      header('Content-type: application/pdf');
      header('Content-Disposition: attachment;filename="'.$_POST['nazev'].'"');
      readfile($_POST['cesta']);
    }
    
     if(isset($_POST['smazanicko_pdf']))
     {
      $probehni="SELECT cesta FROM soubory WHERE jmeno='".$_SESSION['jmeno']."' and nazev='".$_POST['nazev']."' and typ='pdf'";
      $provedeme=$db->query($probehni);
      while($row = $provedeme -> fetch_assoc())
      {
       unlink($row['cesta']);
       $db->query("DELETE FROM soubory WHERE jmeno = '".$_SESSION['jmeno']."'and nazev='".$_POST['nazev']."' and typ='pdf'and cesta='".$_POST['cesta']."'");
       echo("<script>window.location.href=\"\"</script>");
      }
     }