unable to fetch packages on parrot os code example

Example 1: W: Failed to fetch http://deb.parrotsec.org/parrot/dists/stable/InRelease The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B56FFA946EB1660A

nameserver 8.8.8.8

Example 2: W: Failed to fetch http://deb.parrotsec.org/parrot/dists/stable/InRelease The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B56FFA946EB1660A

sudo nano /etc/resolv.conf