Can't download the Public Key

We followed this guide step by step:
h ttps://jitsi.github.io/handbook/docs/devops-guide/devops-guide-quickstart
After executing following comands,
curl https://download.jitsi.org/jitsi-key.gpg.key | sudo sh -c ‘gpg --dearmor > /usr/share/keyrings/jitsi-keyring.gpg’
echo ‘deb [signed-by=/usr/share/keyrings/jitsi-keyring.gpg] https://download.jitsi.org stable/’ | sudo tee /etc/apt/sources.list.d/jitsi-stable.list > /dev/null
apt update does not work correctly anymore. Any fix ? We already checked older topics but that didnt work.
Output is in german so i can realy provide a screenshot but its something about a missing signature and that its missing the NO_PUBKEY EF8B479E2DC1389C

Does this work for you echo 'deb https://download.jitsi.org stable/' | sudo tee /etc/apt/sources.list.d/jitsi-stable.list?

What is the output of this command?

It worked thanks!.

But the interesting part is why the other one did not work. What is the OS and version you used, so I can try reproing?
It will be beneficial to understand the problem and update the docs with a fix.