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) VALUES ('6377891d8b0666073109c27be15228c0', -1, 1215180405, 1215180405, '26673f11', 0, 0)

Line : 152
File : /web/phpBB2/includes/sessions.php