Action server not working with Docker: Couldn't connect to the server

We created our own docker images and Dockerfiles now (seperate ones for rasa server and action server) instead of using the latest versions from Rasa docker hub. We managed to start both servers on Heroku, but now we have port issues with the CMD run commands in the Dockerfiles. Heroku ads “” in front of the ports. The solution presented here did not solve the issue for us: Deploy bot on Heroku