Error when running the Vagrant

[Milindu Sanoj Kumarage]

I'm getting an erros which says

W: GPG error: https://repo.saltstack.com trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 0E08A149DE57BFBE

and

gpgkeys: https fetch error 7: Failed to connect to repo.saltstack.com port 443: Network is unreachable
gpg: no valid OpenPGP data found.

I tried several time, but it is still same. how can I get this fixed?

I'm on Ubuntu 18.04.1 LTS 64-bit

[Milindu Sanoj Kumarage]

@hannahcin @ThisIsJohnBrown @matthewgoshman @vgpena Please help :)