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 ('9f6b71d647f36234ad34860e5c5b91d4', -1, 1714000464, 1714000464, '12de756d', -4, 0, 0)

Line : 187
File : sessions.php