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 ('7f35f045005c90aeed782f71d9bd0431', -1, 1708740776, 1708740776, '23afc9bf', -10, 0, 0)

Line : 187
File : sessions.php