Debugging Bounce Detection

Hello, i’m implementing an OOB/FBL receiver in kumomta and am trying to troubleshoot why an OOB response might not get generated on a bounce message. We’re using the socketlabs bounce tester which generates a bounce to the return-path. The email is getting to the receiving server and being accepted but it’s only generating a Reception and Delivery event.

We are using the lua helpers, here is our listener_domains.toml if that helps:

log_oob = true
log_arf = true
relay_to = false

["fbl.my-domain.com"]
log_oob = true
log_arf = true
relay_to = false```

Is there a way to see in tracing how and why the OOB may not have been detected?  I can include the trace-smtp-server for the bounce message from SL if that helps too.

Thanks!

The server trace might be helpful