Err:1 http://nginx.org/packages/mainline/ubuntu bionic InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY ABF5BD827BD9BF62
Hit:5 http://security.ubuntu.com/ubuntu bionic-security InRelease
Get:6 http://apt.vestacp.com/bionic bionic InRelease [2,187 B]
Err:6 http://apt.vestacp.com/bionic bionic InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 42C5B2130A1F7714
Reading package lists... Done
W: GPG error: http://nginx.org/packages/mainline/ubuntu bionic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY ABF5BD827BD9BF62
E: The repository 'http://nginx.org/packages/mainline/ubuntu bionic 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: GPG error: http://apt.vestacp.com/bionic bionic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 42C5B2130A1F7714
E: The repository 'http://apt.vestacp.com/bionic bionic 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