I have a problem with Push notifications which works sometimes and just stops working after a while when a user is no longer using the app. My app registers for push notification with Azure using Web API 2.0 back end when it launches . After a user has successfully logged in to the app , it then updates the registration record to add the username as Tag . According to my knowledge Azure registration has a long life span which is supposed to be sometime in 9999/12/31 23:59:59. My question is , Does both PNS handlers for Android FCM and IOS APNS expires , If they do how can I register the app with Azure again if the user is not using the app for sometime so they wont miss notifications?