phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 'session_user_id'

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('40f76ac9285eebc359f7d5694667fe50', -1, 1591107277, 1591107277, '12cebb51', 0, 0, 0)

Line : 187
File : sessions.php