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 ('ac56f71f2d1310b4e353a55e5340e5b7', -1, 1711713416, 1711713416, '0351b8aa', -7, 0, 0)

Line : 187
File : sessions.php