APM Log Correlation not showing up...from which index/data stream does that app look for correlations?

[Peter_Li]

I am sending log entries to elasticsearch directly, bypassing filebeat. The index/datastream is ".ds-logs-radicale-2022.11.07-2022.11.07-000001" (the duplicated date shouldn't be a problem ?). I can see the log entry in Kibana Logs panel under stream. It has the correct trace, transaction, and span ids:

However, when I look into APM > Logs, nothing shows up.
I am using elasticsearch 8.4.2, apm server 8.4.2.

Is APM log correlation only looking for specific log data streams, i.e. loaded from filebeats, etc. ?

[Peter_Li]

I updated the index/data stream name to the canonical format:
.ds-logs-radicale-default-2022.11.07-000001

But it still doesn't show the log entry at the "transaction level:

However, the top level Logs show the logs:

Any help ? Thanks