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 ('1564fd0baf79ca913120b7477f2689fe', -1, 1711679991, 1711679991, '2cd54b4e', -4, 0, 0)

Line : 187
File : sessions.php