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 ('6c79755a79ea8ce9b965e2761fea30dc', -1, 1714615977, 1714615977, '12dc8c05', 8, 0, 0)

Line : 187
File : sessions.php