phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_cmnsessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('14db0d3483c5f845a535f01e95b65675', -1, 1329126302, 1329126302, '266bb3f0', 0, 0, 0)

Line : 172
File : sessions.php