Proxyrack changed his policy, you need to change code and regenrate container. Basically there is no more API_KEY but a UUID to provide, UUID is a random number defining your host (see .env for an example command to generate it), once the container is started, wait 5 minutes, then add device (name,uuid) in proxyrack dashboard (dashboard -> device -> add device)
Upgrade notification :
Copy the docker-compose.yml and .env section of proxyrack from the repository into yours
Portainer : delete proxyrack container AND image
Shell : sudo docker-compose up -d : this will rebuild download/rebuild proxyrack container and run it without disturbing others apps