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 ('5f0e0d8cb591452d5af99a9d6cbee09b', -1, 1419231569, 1419231569, '3691b7a9', 0, 0)

Line : 158
File : sessions.php