Ask What do you check first when users report duplicate push notifications for one event?

[Dean101]

When users report duplicate push notifications for one event, I first check the event-to-notification mapping in the delivery logs. That usually reveals whether the backend is creating multiple notification jobs for the same event ID or if retries from the queue are being treated as new sends. I also compare user tokens and device registrations to see if the same user is subscribed more than once through different sessions or cached states. Finally, I inspect deduplication keys and timestamp windows to confirm whether the system is failing to suppress near-identical events within the expected time threshold.