DVGA not accessible from apollo studio?

I am just trying out DVGA (https://github.com/dolevf/Damn-Vulnerable-GraphQL-Application) and I hosted the app on a EC2 and open port 5013

docker run -d -t -p 5013:5013 -e WEB_HOST=0.0.0.0 --name dvga dvga

I understand DVGA enabled introspection by default and $ec2HOST:5013 is accessible from my browser. However, from apollo studio, URL $ec2HOST:5013/graphql is not accessible. why?