phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb2_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('c0355566e0dd21df0fd0383b5f51c4d3', -1, 1596550439, 1596550439, '03ec9f82', 0, 0, 0)

Line : 187
File : sessions.php