apt.armbian.com bookworm release not signed error

[kjs]

Just updated many armbian files shown as available for update. After the update sudo apt update shows the error message:

E: The repository 'http://apt.armbian.com bookworm Release' is no longer 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.

How can I fix this or was signing simply forgotten?

Thank you!

[SteeMan]

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