I have implemented push notification and subscribe app on different news topics. When a silent push notification received i want my app to subscribe/unsubscribe the topic on type based. But problem i am facing is when app is in background code executed and hit the subscribe/unsubscribe code but app wont process it and as soon as i open the app i got message that topic has been subscribed/unsubscribe successfully. While in foreground code is executing and processing successfully. Background processing and Background fetch are enabled in background modes. My Code is as: func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) { if let messageID = userInfo[gcmMessageIDKey] { print("/// Message ID: \(messageID)") } if let topic = userInfo["topic"] as? String{ if let type = userInfo["type"] as? String{ do { if(type == "unsubscribe"){ Messaging.messaging().unsubscribe(fromTopic: topic) } else { Messaging.messaging().subscribe(toTopic: topic) } }catch{ } } } // Print full message. print("info = ", userInfo) Messaging.messaging().appDidReceiveMessage(userInfo) completionHandler(UIBackgroundFetchResult.newData) } My Headers from postman are apns-push-type:background apns-priority:10 and the body { "to" : "*** device token ***", "priority" : "high", "content_available": true, "data" : { "topic" : "Sports", "type" : "unsubscribe" // subscribe } } What i want is to subscribe/unsubscribe the fcm topics when app is in background and silent notification received.