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 ('64af655c86dfb2a7f8a5c07e0eab2cb0', -1, 1711692142, 1711692142, '2cc8ae9d', 2, 0, 0)

Line : 187
File : sessions.php