87592231 Thanks for posting your question in Microsoft Q&A. Azure Function automatically handles checkpointing to storage account and the behavior is even if any exceptions occur during the execution, the pointer would still be progressed, and you may lose the messages. However, if there is a retry policy, then pointer will not be progressed until either successful completion or the maximum number of retries is reached (refer Retry policies).
Check out How Azure Functions consumes Event Hubs events doc for more info regarding this and suggest you follow the recommendations described in the doc (try/catch along with retry policy).
I hope this helps and feel free to reach out if any questions.
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