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 ('e8cc069b91e191d038e6e524f8de1352', -1, 1711699937, 1711699937, '36ea921a', -4, 0, 0)

Line : 187
File : sessions.php