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 ('2a2395db755c9cb0cc9dd9fc133d39fe', -1, 1722048480, 1722048480, '0391b083', -8, 0, 0)

Line : 172
File : /home/rebkell/public_html/boards/includes/sessions.php