I’m with you on that one!
I re-read my message: I didn’t meant to say, that the BIND_IP solved my problem. That’s was just the first suggestion. The second suggestion was to check if the containers are in the same network (they weren’t).
So it was a networking issue within/between the containers. The traefik container was in a different network. I confirmed that by manually disconnecting and connecting it to the correct network. That was the solution.
Then I went through the .yml, defined the network there and made sure everything connects to it (without copy-paste from ChatGPT – it’s suggestions would’ve broken everything).
But: ChatGPT helped my find out what the issue was faster then my manual RTFM ever would!