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 ('684655e8b9f9805af451842a774b7c95', -1, 1490400038, 1490400038, '32106160', -4, 0, 0)

Line : 187
File : sessions.php