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 ('b6f804bb959f4a8e0bf88c865d37146c', -1, 1714613191, 1714613191, '0391177b', -4, 0, 0)

Line : 187
File : sessions.php