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 ('863758d9a95ad1fc534fcdcf1b416724', -1, 1711640607, 1711640607, '03ebf32d', 6, 0, 0)

Line : 187
File : sessions.php