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 ('91166ea7de2f5f7af5f163e467f4d002', -1, 1713512127, 1713512127, '1275c4b8', -4, 0, 0)

Line : 187
File : sessions.php