debian stretch Sources update error,can anyone support?

[justzx <justzx2011@gmail.com>]

Error message:

Ign:39 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/non-free Sources
Ign:40 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/contrib Sources
Ign:41 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/main amd64 Packages
Ign:42 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/main all Packages
Ign:43 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/main Translation-en
Ign:44 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/main Translation-en_US
Ign:45 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/contrib all Packages
Ign:46 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/contrib amd64 Packages
Ign:47 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/contrib Translation-en_US
Ign:48 http://cdn-fastly.deb.debian.org/debian-security stretch/updates/contrib Translation-en
Reading package lists... Done
W: The repository 'http://cdn-fastly.deb.debian.org/debian-current stretch-backports Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: The repository 'http://cdn-fastly.deb.debian.org/debian-current stretch Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: The repository 'http://cdn-fastly.deb.debian.org/debian-security stretch/updates Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch http://cdn-fastly.deb.debian.org/debian-current/dists/stretch-backports/main/source/Sources  404  Not Found
E: Failed to fetch http://cdn-fastly.deb.debian.org/debian-current/dists/stretch/non-free/source/Sources  404  Not Found
E: Failed to fetch http://cdn-fastly.deb.debian.org/debian-security/dists/stretch/updates/main/source/Sources  404  Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.