W: GPG error: http://deb.xanmod.org releases InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 86F7D09EE734E623
E: The repository 'http://deb.xanmod.org releases 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.
root:~# wget -qO - https://dl.xanmod.org/archive.key | sudo gpg --dearmor -o /usr/share/keyrings/xanmod-archive-keyring.gpg
File '/usr/share/keyrings/xanmod-archive-keyring.gpg' exists. Overwrite? (y/N) y
gpg: no valid OpenPGP data found.
W: GPG error: http://deb.xanmod.org releases InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 86F7D09EE734E623
E: The repository 'http://deb.xanmod.org releases 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.
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
E: Unable to locate package linux-xanmod-lts-x64v3