MongoDB installation in Vagrant

I’m receiving a gpg key error during vagrant up --provision command.

gpg: requesting key A15703C6 from hkp server keyserver.ubuntu.com
gpgkeys: key 0C49F3730359A14518585931BC711F9BA15703C6 can’t be retrieved
gpg:
no valid OpenPGP data found.
gpg:
Total number processed: 0