Issue PPE - repository GPG Error

[LRLD]

Server operating system version

Ubuntu 24.04.2

Plesk version and microupdate number

Plesk Obsidian 18.0.70 Update #2 Web Pro Edition

Hi,

as the title suggests, I'm currently getting the following error...

Err:14 https://mirror.apheleia-it.ch/repos/Kolab:/16/Ubuntu_24.04_Plesk_17  InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY C8B3DA4DF6491D3D
Fetched 1,037 kB in 1s (1,490 kB/s)
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
5 packages can be upgraded. Run 'apt list --upgradable' to see them.
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://mirror.apheleia-it.ch/repos/Kolab:/16/Ubuntu_24.04_Plesk_17  InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY C8B3DA4DF6491D3D
W: Failed to fetch https://mirror.apheleia-it.ch/repos/Kolab:/16/Ubuntu_24.04_Plesk_17/InRelease  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY C8B3DA4DF6491D3D
W: Some index files failed to download. They have been ignored, or old ones used instead.

I do see a kolab.gpg in /etc/apt/trusted.gpg.d, but there's nothing in the /etc/apt/keyrings folder.
Any ideas?

TIA

 

[scsa20]

Have you tried downloading the key?

sudo gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys C8B3DA4DF6491D3D
sudo apt clean