Private Networking does not work.

I created two droplet. A and B. All from scratch and Private IP enabled.

When I ssh into A, ping to Private IP of B fails. When I ssh into B, ping to Private IP of A fails.

I've followed the tutorial provided: How To Set Up And Use DigitalOcean Private Networking and it still fails. I have removed all the rules from firewall and it still fails.

Here is what I get when I ping:

$ ping PRIVATE_IP
PING PRIVATE_IP (PRIVATE_IP) 56(84) bytes of data.
From PRIVATE_IP icmp_seq=1 Destination Host Unreachable
From PRIVATE_IP icmp_seq=2 Destination Host Unreachable
From PRIVATE_IP icmp_seq=3 Destination Host Unreachable

Note that pinging the public ip works. But I am setting up a private network in NYC1 datacenter and it doesn't help.

This is on a Ubuntu 16.04 LTS droplet.
Also all the droplets are created from the same Digitalocean account.