pswRegister.php

 <?php

require_once("connection.php");

$psw=sha1($_POST['psw']);

if(!isset($_SESSION)){

    session_start();

}

$idUsername=$_SESSION['idUsername'];

$sql="DELETE FROM token WHERE idUsername = $idUsername LIMIT 1";

mysqli_query($con, $sql) or die($sql);

$sql="INSERT INTO psw (idUsername, psw) VALUES ($idUsername, '$psw')";

mysqli_query($con, $sql) or die($sql);

unset($_SESSION['idUsername']);

mysqli_close($con);

header("Location:login.html?msg=passwordRecuperada");

?>