Elastic APM not capturing traces, but metrics are visible for WSO2 application

Question

I have configured Elastic APM to monitor my WSO2-based API, and while I can see metrics, I'm unable to capture traces. I've followed the setup instructions and checked various configuration settings, but traces are not appearing. Here's what I've done,

1. I added the Elastic APM Java Agent to the micro-integrator.sh and configured as follows.

while [ "$status" = "$START_EXIT_STATUS" ]
do
    $JAVACMD \
    .....
    -javaagent:/path/to/elastic-apm-agent-1.43.0.jar \
    -Delastic.apm.service_name=tracing-service \
    -Delastic.apm.application_packages=com.example \
    -Delastic.apm.environment=develop \
    -Delastic.apm.server_urls=http://127.0.0.1:8200 \
    org.wso2.micro.integrator.bootstrap.Bootstrap $*
    status=$?
done

2. I don't see any errors or warnings in my application or Elastic APM agent logs.
3. Despite these efforts, I can only see metrics in the Elastic APM UI but no traces. I'd like to capture traces. What could be causing this issue, and how can I resolve it?

Any guidance or suggestions on troubleshooting this issue would be greatly appreciated.