phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO docttorrdiscluc_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('cc6b060f39da7ce844933c3c958b7b4e', -1, 1544631138, 1544631138, '36e2243c', -4, 0, 0)

Line : 190
File : sessions.php