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 ('4251f0667c3c2f78dba38d5f52253f97', -1, 1757040462, 1757040462, 'd849d80f', 22, 0, 0)

Line : 247
File : sessions.php