debian stretch/updates Release' does not have a Release file

[TommyK]

After I tried the hotfix today I keep gettin this in my logs;

W: The repository 'http://mirrors.digitalocean.com/debian 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://mirrors.digitalocean.com/debian/dists/stretch/updates/main/source/Sources  404  Not Found [IP: 104.24.117.209 80]
E: Some index files failed to download. They have been ignored, or old ones used instead.

/etc/apt/sources.list.d/3cxpbx-testing.list

deb [arch=amd64] http://downloads-global.3cx.com/downloads/debian stretch-testing main

/etc/apt/sources.list.d/3cxpbx.list

deb http://downloads-global.3cx.com/downloads/debian stretch main

/etc/apt/sources.list

deb http://mirrors.digitalocean.com/debian stretch main contrib non-free
deb-src http://mirrors.digitalocean.com/debian stretch main contrib non-free
deb http://mirrors.digitalocean.com/debian stretch/updates main contrib non-free
deb-src http://mirrors.digitalocean.com/debian stretch/updates main contrib non-free
deb http://mirrors.digitalocean.com/debian stretch-updates main contrib non-free
deb-src http://mirrors.digitalocean.com/debian stretch-updates main contrib non-free