phpBB : Critical Error

Error creating new session

DEBUG MODE

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

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('e1870702e4d4b0f8f1fec27953ed7b86', -1, 1571327322, 1571327322, '22ecd85d', 19, 0, 0)

Line : 191
File : sessions.php