phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO iabb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('47b02a7e986f79bd1ad7a7a642968aa0', -1, 1560910124, 1560910124, '36a11ff7', -4, 0, 0)

Line : 187
File : sessions.php