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 ('f20bae495ddb2b8f08b720f8e6bd68e0', -1, 1714000147, 1714000147, '0387b759', -7, 0, 0)

Line : 187
File : sessions.php