How to fix «gpg: keyserver receive failed: Server indicated a failure» for ``keys.gnupg.net?

2023-08-07--05-56-03

apt-key adv --keyserver keys.gnupg.net --recv-keys 8C718D3B5072E1F5

Executing: /tmp/apt-key-gpghome.jUSXwLg50e/gpg.1.sh --keyserver keys.gnupg.net --recv-keys 8C718D3B5072E1F5
gpg: keyserver receive failed: Server indicated a failure

Use keyserver.ubuntu.com as --keyserver:

apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 8C718D3B5072E1F5

askubuntu.com/questions/1120363#comment2377245_1141364

How did I fix «key 8C718D3B5072E1F5» / «duplicate signatures removed» / «unchanged: 1» on Debian 10 (Buster)?