It appears that this domain is currently pointed to a namecheap DNS server. The domain does resolve correctly however.
It looks like you registered this domain recently and when this question was posted it is likely that the new domain registration had not yet propagated to your ISPs DNS servers. This process can take up to 24-48 hours in some cases and until it is done, your domain may not be resolvable from some ISP networks.
To point the domain at your droplets you have two options:
1.) Use Namecheap's DNS and create an A record that points at your droplet's IP address.
2.) Point your domain to DigitalOcean's DNS servers and create an A record pointing to your droplet. This guide will help.
You should see the same results from either of these options in most cases and both namecheap and DO offer basic DNS services free of charge.
This article explains how to manage your DNS records using the DigitalOcean Control Panel and can help you decide if DigitalOcean's DNS management tools are right for your situation.