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 ('6de04ca5bce275849e7a5a06d8e5c228', -1, 1569047923, 1569047923, '23afbf96', 14, 0, 0)

Line : 187
File : sessions.php