pghero - Getting error while launching postgres through ec2 instance

I created a new ec2 instance and installed docker and tried connecting pgHero to my postgreSQL instance. I have connectivity to postgres through my ec2 instance but i am getting the following error when i access pgHero.

could not translate host name <DB URL> to address: Name or service not known

However, using the same docker image I am able to connect to pghero on my local. Thanks in advance!