When payment gateway like payumoney, ccavenue, paytm etc. redirect to callback url or redirect url or you can say that after payment success or failure we are able to collect data from gateway but unfortunately session destroy automatically sometimes. Sometimes i am able to collect session data and sometimes it destroy all the session data. As i check, session actually not destroy but it creates a new session file or regenerate a session id. There no white space, no special characters also i have tried to store session in database but not helpful.
Also changed the system/libraries/session/session.php
i have also tried this session destroying in codeigniter after redirecting