Key signing on Ubuntu 21.04 is disfunctional

[T145]

user@desk:~/Desktop$ sudo apt-key adv --keyserver hkp://packages.renjin.org:80 --recv-keys EB2514FC345926E9
Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
Executing: /tmp/apt-key-gpghome.WtKmCJVULN/gpg.1.sh --keyserver hkp://packages.renjin.org:80 --recv-keys EB2514FC345926E9
gpg: key EB2514FC345926E9: public key "Renjin Repository Signing Key <support@renjin.org>" imported
gpg: Total number processed: 1
gpg:               imported: 1
user@desk:~/Desktop$ echo deb http://packages.renjin.org/repo/apt stable main | sudo tee /etc/apt/sources.list.d/renjin.list
deb http://packages.renjin.org/repo/apt stable main
user@desk:~/Desktop$ sudo apt-get update
Hit:1 http://us.archive.ubuntu.com/ubuntu impish InRelease
Hit:2 http://us.archive.ubuntu.com/ubuntu impish-updates InRelease         
Get:3 http://security.ubuntu.com/ubuntu impish-security InRelease [99.5 kB]
Get:4 http://packages.renjin.org/repo/apt stable InRelease [1,989 B]           
Hit:5 http://us.archive.ubuntu.com/ubuntu impish-backports InRelease           
Err:4 http://packages.renjin.org/repo/apt stable InRelease
  The following signatures were invalid: EXPKEYSIG EB2514FC345926E9 Renjin Repository Signing Key <support@renjin.org>
Reading package lists... Done
W: GPG error: http://packages.renjin.org/repo/apt stable InRelease: The following signatures were invalid: EXPKEYSIG EB2514FC345926E9 Renjin Repository Signing Key <support@renjin.org>
E: The repository 'http://packages.renjin.org/repo/apt stable InRelease' is not signed.
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.

New format: https://www.linuxuprising.com/2021/01/apt-key-is-deprecated-how-to-add.html