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 ('ef663a86bef8e34f682f60e061d1f228', -1, 1709280171, 1709280171, '2cc014f0', -10, 0, 0)

Line : 187
File : sessions.php