There may be cases where you see multiple step_started events for the same step in a workflow run. This happens if the function invocation executing the step crashes unexpectedly, and the step can not report the error. The step will be re-tried according to your retry policy in this case, but no error will be visible in the Observability UI.

• Function timeouts: if your step code runs longer than the configured maximum function duration, it will be killed. Compare the gap between the step_started events to your configured function duration to be sure.
• Out of memory (OOM): if your step code loads enough data into memory, especially if the step is invoked concurrently, the function invocation might run out of memory. You can see your function's peak memory use by going to the Observability Query page and showing the Function Invocation Peak Memory metric, then filtering down the Route to /.well-known/workflow endpoints.
• Network issues: persistent firewall, network stability, and related issues might prevent your function from reporting results or errors. This should be temporary.

If you consistently see multiple step_started events and have ruled out function timeouts, OOMs, and firewall issues, please contact support.