I created a php with a tutorial on the internet and it used to work but suddenly it has stopped working. If you can help me, thank you. there goes the code:
<?php
if(isset($_SESSION['id'])) {
header("Location: user.php");
}
if(isset($_POST['register'])) {
$db = mysqli_connect("localhost", "nunomarquina", "Amaral47",
"proyecto_ets2mp");
$username = strip_tags($_POST['username']);
$password = strip_tags($_POST['password']);
$password_confirm = strip_tags($_POST['password_confirm']);
$mail = strip_tags($_POST['email']);
$username = stripslashes($username);
$password = stripslashes($password);
$password_confirm = stripslashes($password_confirm);
$mail = stripslashes($mail);
$username = mysqli_real_escape_string($db, $username);
$password = mysqli_real_escape_string($db, $password);
$password_confirm = mysqli_real_escape_string($db, $password_confirm);
$mail = mysqli_real_escape_string($db, $mail);
$password = md5($password);
$password_confirm = md5($password_confirm);
$sql_store = "INSERT INTO users (username, password, email) VALUES ('$username', '$password', '$mail')";
$sql_fetch_username = "SELECT username FROM users WHERE username = '$username'";
$sql_fetch_mail = "SELECT email FROM users WHERE email = '$mail'";
$query_username = mysqli_query($db, $sql_fetch_username);
$query_mail = mysqli_query($db, $sql_fetch_mail);
}
?>
<!doctype html>
<html>
<head>
<link rel="stylesheet" href="assets/css/main.css"/>
<title>Register form</title>
</head>
<body>
<div id="login">
<h1>Register</h1>
<form action="register.php" method="post" enctype="multipart/form-data">
<input placeholder="Username" name="username" type="text">
<input placeholder="Password" name="password" type="password">
<input placeholder="Confirm Password" name="password_confirm" type="password">
<input placeholder="E-Mail Adress" name="email" type="text">
<input name="register" type="submit" value="Register">
</form>
<h2>Tienes una cuenta?</h2>
<h2><a href="login.php">Inicia Sesion</a></h2>
</div>
</body>
</html>