invana-studio: invana-studio doesn't connect to invana-engine using docker compose

This is my docker compose file

version: '3'

volumes: 
    janusgraph-default-data:

services:
    janusgraph:
        image: docker.io/janusgraph/janusgraph:latest
        container_name: janusgraph
        ports:
            - "8182:8182"
        # The mounted volume only makes sense if JanusGraph is being run with the BerekeleyDB storage.
        volumes:
            - "janusgraph-default-data:/var/lib/janusgraph"

    invanaui:
        image: invanalabs/invana-studio
        container_name: invana-studio
        ports:
            - "8888:8888"

    invanaengine:
        image: invanalabs/invana-engine
        container_name: invana-engine
        ports:
            - "8200:8200"
        environment:
            - GREMLIN_SERVER_URL=ws://janusgraph:8182/gremlin

When I try connecting to the invana-engine, I tried both ‘http://localhost:8200/graphql’ and ‘http://invanaengine:8200/graphql’

Both didn’t work. The url shows ‘http://invana-studio.herokuapp.com/connect?error=Failed to connect&transporterStatus=999’

Am I doing anything wrong? My janus graph is working and I am able to execute Gremlin queries on it via my node.js app