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 ('9a1d8f8dada0e2f98306d78a4df0b163', -1, 1709408246, 1709408246, '12cf81af', -4, 0, 0)

Line : 187
File : sessions.php