Once you've added your API keys to GridPane, creating new servers should work correctly out of the box.
If, however, you've setup a cloud firewall at either DigitalOcean or Vultr, you may need to whitelist our IP addresses in order to spin up a server. This is only necessary if you've setup a cloud firewall.
To whitelist us, head to your firewall setup and add the following two IP addresses to your whitelist: 18.104.22.168 and 22.214.171.124.
Please check out the following articles from each provider for more information.