Err:6 https://production.repo.droidian.org bullseye InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY A1ED3DBEFB35F3C5
Reading package lists... Done
W: GPG error: https://production.repo.droidian.org bullseye InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY A1ED3DBEFB35F3C5
E: The repository 'https://production.repo.droidian.org bullseye 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.