Hi,
Are you using a notification filter? When a notification is filtered out in the notification filter, then the notification could be offered again to the notification filter at a later time. We recommend altering the notification there and letting Plot send the notification instead of sending a notification yourself. You can alter all the properties of the local notification there. Is there a reason why that wouldn't work in your case?
If you really don't want to alter the notifications, then we recommend using geotriggers. A disadvantage would be that we then won't be able to provide notification statistics.
We don't support handleNotification: for notifications other than notifications generated by Plot.
Please let me know if something is still unclear or if you have further questions.