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 ('6875c9bb1f90a05f8421f58c6040b776', -1, 1713508036, 1713508036, '0311a2f7', -8, 0, 0)

Line : 187
File : sessions.php