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 ('142902aa74b7c15ff8070a3d34f0ccd8', -1, 1780552108, 1780552108, 'd849d893', 2, 0, 0)

Line : 189
File : sessions.php