running multiple services on same port in docker-compsoe

We have multiple microservices that are run on port 8080. As far as I know that only 1 service can run on port 8080.

Would it mean running the microservice as a port: 8080:8081 or 8081:8081?

Below are the services that we are trying to implement in docker-compose

reference-service:
  image: **
  ports:
    - "8080:8080"

test-service:
    image: **
    ports:
      - "8080:8081"

Source: Docker Questions