Please help -everything even HTTPS worked for minutes now internal server error on every backend

As the title says, I had my traefik reverse proxy setup seemingly working great last night. Got the dashboard up and I could access my portainer container. Enabled HTTPS with certificates via Letsencrypt and everything still worked great via traefik.mydomain.me and portainer.mydomain.me. For good measure I copy my traefik.toml and docker-compose.yml to my local PC for backup before making more changes so I have a "known good" baseline.

Added fail2ban and watchtower. Up again and now the traefik dashboard still works, but when I try to go to portainer.mydomain.me I get a page that says "Internal server error" I try backing that out manually, then after it fails I copy the backups back to my docker host, but I'm still running into this issue. My theory is that it is a https frontend to backend issue, but I can't see anything in the logs - maybe I'm looking in the wrong place.

Can someone help me get this working? I have a .env filling in some basic details like my user dir and domain, and I note my rules.toml is still 0 bytes but I think that's maybe normal. I did also note that now, at least, while the dash shows the 2 frontends with http and https entrypoints (traefik and portainer) and 2 backends, the trafik backend is showing http and the portainer backend shows https. Not sure if that's a clue. Other than that, here is what I have:

traefik.toml

docker-compose.yml

So I've figured it out. I had this line in the section for my backend container:

      - "traefik.protocol=https"

Commenting that out resolved the error. I really suspected it was something like this all along, I just wish I hadn't overlooked that line a dozen times and I wish the "Internal server error" or container logs had made it clearer that this was the issue, as I would imagine this is hugely common. Anyway, onward and upward!