PHP session not destroying or unsetting - php

Question

I have this following PHP code for checking login in my index.php
<?php
session_start();
$con = mysqli_connect("***", "***", "***", "***");
$fbid_check=$_SESSION['loginid_session'];
$fbphoto_session=$_SESSION['loginphoto_session'];
$fbname_sql=mysqli_query($con, "SELECT fb_name FROM uni_users WHERE fb_id='$fbid_check' ");
$name_fetch=mysqli_fetch_array($fbname_sql, MYSQLI_ASSOC);
$fbname_session=$name_fetch['fb_name'];
if(isset($fbname_session))
{
header("location: http://www.uniwink.com/landing/profile.php");
}
mysqli_close($con);
?>
This checks for login and redirects to profile.php which has the following PHP code in the header to check for login
<?php
$con = mysqli_connect("****", "****", "****", "****");
session_start();
$fbid_check=$_SESSION['loginid_session'];
$fbphoto_session=$_SESSION['loginphoto_session'];
$fbname_sql=mysqli_query($con, "SELECT fb_name FROM uni_users WHERE fb_id='$fbid_check' ");
$name_fetch=mysqli_fetch_array($fbname_sql, MYSQLI_ASSOC);
$fbname_session=$name_fetch['fb_name'];
if(!isset($fbname_session))
{
header("location: http://www.uniwink.com/landing");
}
mysqli_close($con);
?>
And I have this following logout.php which is called from profile.php
<?php
session_start();
unset($_SESSION['loginid_session']);
unset($fbname_session);
session_destroy();
header("location: http://www.uniwink.com/landing");
exit();
?>
The problem is after logout, it still goes into profile.php . It is as if like the session is not destroyed at all. The thing is it was working properly until yesterday and happened all of a sudden. Thanks

Answer 1

try to move session_start(); above the mysql connection.
change
$con = mysqli_connect("****", "****", "****", "****");
session_start();
to
session_start();
$con = mysqli_connect("****", "****", "****", "****");
also use isset with session
if (isset($_SESSION['loginid_session'])){
.....
}

Answer 2

try adding the following to your logout;
$_SESSION = array();
if (ini_get("session.use_cookies"))
{
$params = session_get_cookie_params();
setcookie(session_name(), '', time() - 42000,
$params["path"], $params["domain"],
$params["secure"], $params["httponly"]
);
}
Note: This will destroy the session - not just the session data.

Answer 3

Check for the session.
if (isset($_SESSION['loginid_session']))
{
header("location: http://www.uniwink.com/landing/profile.php");
}
else
{
header("location: http://www.uniwink.com/landing");
}