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 ('81b9e57001c3a7eb4ae75b056102b8a4', -1, 1329088680, 1329088680, '266bb3ec', -7, 0, 0)

Line : 189
File : sessions.php