thanks, i did already but the manual of theml doesnt really works. i always got the some error message "cant lokate package
i still wait for support answer of them (i did forget to mention, that i use os kali)
here the bash protocoll
──(root㉿kali-raspberry-pi5)-[/etc/apt/sources.list.d]
└─# sudo apt-get update
Hit:1
http://kali.download/kali kali-rolling InRelease
Get:2
https://repo.nordvpn.com/deb/nordvpn/debian stable InRelease [5,305 B]
Err:2
https://repo.nordvpn.com/deb/nordvpn/debian stable InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6B219E535C964CA1
Reading package lists... Done
W: GPG error:
https://repo.nordvpn.com/deb/nordvpn/debian stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6B219E535C964CA1
E: The repository '
https://repo.nordvpn.com/deb/nordvpn/debian stable 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㉿kali-raspberry-pi5)-[/etc/apt/sources.list.d]
└─# sudo apt-get install nordvpn
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
E: Unable to locate package nordvpn