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 ('e856ac2b4cb063953b84b1fb7b1aa8ad', -1, 1714003791, 1714003791, '12e2bb18', 4, 0, 0)

Line : 187
File : sessions.php