How fast is it responding and what speed are you expecting? The speed is going to come down to resources and what the workflow is actually doing but typically 1GB / 1 Core would be enough for some basic tasks and should result in a fairly quick response.
I did a quick test on a basic Digital Ocean droplet and I was getting a reply back in under a second with a simple response.
I have n8n running through docker compose. I just inserted the option into the .env file, then executed the docker-compose down command and launched the docker-compose up -d command
So in that set up Traefik is a reverse proxy but should be ok, can you add the execution process option to the environment section of the compose file and stop the container then start it again this should in theory fix the issue.