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 ('7c58f58ea6079df5b9cde91bec69cf18', -1, 1211051869, 1211051869, '26673f12', 0, 0, 0)

Line : 185
File : sessions.php