There are certain instances where an app that has push capabilities stops leveraging Apple’s Push Notification Services (APNS). This can happen for a few different reasons. But there’s no error correcting for this process and so occasionally, you’ll want to reset the app back to what amounts to a factory default status, in order to get Push working again. The first time an app is opened, it will register for push notifications and prompt for receiving push notifications for the app. This prompt never occurs again unless the app is uninstalled for a minimum of a day and then reinstalled. You can duplicate this functionality by simply deleting the app and then installing the app again after setting the Date & Time manually a day ahead of the current date.