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 ('4fd5f8b70acc9fd361f14500745ef22a', -1, 1542437881, 1542437881, '3692c318', 1, 0, 0)

Line : 190
File : sessions.php