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 ('773e9409b9b0ede455201ae7420b1bb0', -1, 1711619661, 1711619661, '03ed2e78', -4, 0, 0)

Line : 187
File : sessions.php