phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO mex2mex_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in) VALUES ('aad1ff5c79bbaa47f52066f7352475b7', -1, 1223838481, 1223838481, '26673f3b', 25, 0)

Line : 170
File : sessions.php