I just answered your topic here:
What you could try is to start instead with:
sudo docker-compose up -d
just with:
sudo docker-compose up
If you do that you should see the output of the processes. Mainly traefik as it looks like the problem is related to it. It seems not to be able to create the SSL certificate with letsencrypt and so probably does also not serve n8n correctly.
Just to be 100% sure. Did you set the values in the .env file correctly?
...
# The top level domain to serve from
DOMAIN_NAME=bttrr.com
# The subdomain to serve from
SUBDOMAIN=n8n
...