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 ('8248839f8520d4c2e521da783101d6bf', -1, 1711718297, 1711718297, '2cc5eede', -4, 0, 0)

Line : 187
File : sessions.php