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 ('646f8a54c5b0d75c80c33bc88c1ed7aa', -1, 1711659910, 1711659910, '2cc32fe3', -10, 0, 0)

Line : 187
File : sessions.php