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 ('8a771fb9ec0405d816b94e4d2e28456d', -1, 1542177828, 1542177828, '36dd4b73', -4, 0, 0)

Line : 190
File : sessions.php