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 ('86121ca91c9b6991eabec55c9b1616f8', -1, 1708744073, 1708744073, '23afc9bf', -1, 0, 0)

Line : 187
File : sessions.php