The "state" param from the URL and session do not match

Question

In facebook documantion

require('include/facebook/autoload.php'); //SDK directory
$fb = new Facebook\Facebook([
'app_id' => '***********',
'app_secret' => '***********************'
]);

$helper = $fb->getRedirectLoginHelper();
$permissions = ['email', 'public_profile']; // optional
$loginUrl = $helper->getLoginUrl('http://www.meusite.com.br/login-callback.php', $permissions);

When direct it to the url $loginUrl, the return is: Facebook SDK returned an error: Cross-site request forgery validation failed. The "state" param from the URL and session do not match

Answer 1

I had the same error.

The problem occurred because I did getLoginUrl(...) before getAccessToken()

So rid of getLoginUrl(...) in redirected URL and code should works.