Armadilloフォーラム

youtube でArmaddillo-IoT G4:debian(buster/stretch)のコンテナを作成する方法をビデオの手順で設定してますが、コンテナの中に入り下記入力しましたがエラーが出てしまいます。ネットワークは接続しております。原因と対処方法をお教えください。
# apt update && upgrade
Ign:1 http://security.debian.org/debian-security stretch/updates InRelease
Err:2 http://security.debian.org/debian-security stretch/updates Release
404 Not Found [IP: 151.101.2.132 80]
Ign:3 http://deb.debian.org/debian stretch InRelease
Ign:4 http://deb.debian.org/debian stretch-updates InRelease
Err:5 http://deb.debian.org/debian stretch Release
404 Not Found [IP: 151.101.90.132 80]
Err:6 http://deb.debian.org/debian stretch-updates Release
404 Not Found [IP: 151.101.90.132 80]
Reading package lists... Done
E: The repository 'http://security.debian.org/debian-security stretch/updates Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://deb.debian.org/debian stretch Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://deb.debian.org/debian stretch-updates Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.