phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO forum_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('7c0ed1e45e899da92393edea1101315c', -1, 1540271119, 1540271119, '365057a6', -4, 0, 0)

Line : 187
File : sessions.php