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 ('e5d6e4c720cc227c8d6c3a5b4bbb6e4e', -1, 1757136900, 1757136900, 'd849d8a2', -9, 0, 0)

Line : 187
File : sessions.php