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 ('58ed73eaa43edd568a0723df71d0d8b1', -1, 1438725268, 1438725268, '36ea3425', -1, 0)

Line : 158
File : sessions.php