A service works correctly when run with `docker run` directly but behaves differently (wrong config, missing env vars) when started via `docker compose up`.

Check whether the compose.yaml is missing `environment:`/`env_file:` entries that were being passed manually via `-e` flags in the direct `docker run` command, or whether a `.env` file in the Compose project directory is silently overriding expected values — `docker compose config` is useful here to print the fully resolved configuration and spot the discrepancy directly.