phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('a5bb79263e1c91ed083ccf375fddff56', -1, 1329160282, 1329160282, '266bb3f0', -6, 0, 0)

Line : 189
File : sessions.php