root@pi:/home/pi# sudo apt update
Hit:1 http://archive.raspberrypi.com/debian bookworm InRelease
Hit:2 http://deb.debian.org/debian bookworm InRelease
Hit:3 http://deb.debian.org/debian-security bookworm-security InRelease
Hit:4 http://deb.debian.org/debian bookworm-updates InRelease
Get:5 https://repos.influxdata.com/debian stretch InRelease [7,048 B]
Hit:6 https://packages.grafana.com/oss/deb stable InRelease
Hit:7 https://deb.nodesource.com/node_18.x nodistro InRelease
Err:5 https://repos.influxdata.com/debian stretch InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D8FF8E1F7DF8B07E
Reading package lists... Done
W: GPG error: https://repos.influxdata.com/debian stretch InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D8FF8E1F7DF8B07E
E: The repository 'https://repos.influxdata.com/debian stretch 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.
W: https://packages.grafana.com/oss/deb/dists/stable/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.