diff --git a/SessionMessagingKit/Jobs/AttachmentDownloadJob.swift b/SessionMessagingKit/Jobs/AttachmentDownloadJob.swift
index 85e251553..b5eb03556 100644
--- a/SessionMessagingKit/Jobs/AttachmentDownloadJob.swift
+++ b/SessionMessagingKit/Jobs/AttachmentDownloadJob.swift
@@ -59,7 +59,9 @@ public final class AttachmentDownloadJob : NSObject, Job, NSCoding { // NSObject
 
     // MARK: Running
     public func execute() {
-        JobQueue.currentlyExecutingJobs.insert(id!)
+        if let id = id {
+            JobQueue.currentlyExecutingJobs.insert(id)
+        }
         guard !isDeferred else { return }
         if TSAttachment.fetch(uniqueId: attachmentID) is TSAttachmentStream {
             // FIXME: It's not clear * how * this happens, but apparently we can get to this point
diff --git a/SessionMessagingKit/Jobs/AttachmentUploadJob.swift b/SessionMessagingKit/Jobs/AttachmentUploadJob.swift
index 584824982..e3f9a1df6 100644
--- a/SessionMessagingKit/Jobs/AttachmentUploadJob.swift
+++ b/SessionMessagingKit/Jobs/AttachmentUploadJob.swift
@@ -60,7 +60,9 @@ public final class AttachmentUploadJob : NSObject, Job, NSCoding { // NSObject/N
 
     // MARK: Running
     public func execute() {
-        JobQueue.currentlyExecutingJobs.insert(id!)
+        if let id = id {
+            JobQueue.currentlyExecutingJobs.insert(id)
+        }
         guard let stream = TSAttachment.fetch(uniqueId: attachmentID) as? TSAttachmentStream else {
             return handleFailure(error: Error.noAttachment)
         }
diff --git a/SessionMessagingKit/Jobs/MessageReceiveJob.swift b/SessionMessagingKit/Jobs/MessageReceiveJob.swift
index 48e919ab8..227dfa591 100644
--- a/SessionMessagingKit/Jobs/MessageReceiveJob.swift
+++ b/SessionMessagingKit/Jobs/MessageReceiveJob.swift
@@ -54,7 +54,9 @@ public final class MessageReceiveJob : NSObject, Job, NSCoding { // NSObject/NSC
     }
     
     public func execute() -> Promise<Void> {
-        JobQueue.currentlyExecutingJobs.insert(id!)
+        if let id = id { // Can be nil (e.g. when background polling)
+            JobQueue.currentlyExecutingJobs.insert(id)
+        }
         let (promise, seal) = Promise<Void>.pending()
         SNMessagingKitConfiguration.shared.storage.write(with: { transaction in // Intentionally capture self
             do {
diff --git a/SessionMessagingKit/Jobs/MessageSendJob.swift b/SessionMessagingKit/Jobs/MessageSendJob.swift
index c894e6460..aed0268a1 100644
--- a/SessionMessagingKit/Jobs/MessageSendJob.swift
+++ b/SessionMessagingKit/Jobs/MessageSendJob.swift
@@ -69,7 +69,9 @@ public final class MessageSendJob : NSObject, Job, NSCoding { // NSObject/NSCodi
 
     // MARK: Running
     public func execute() {
-        JobQueue.currentlyExecutingJobs.insert(id!)
+        if let id = id {
+            JobQueue.currentlyExecutingJobs.insert(id)
+        }
         let storage = SNMessagingKitConfiguration.shared.storage
         if let message = message as? VisibleMessage {
             guard TSOutgoingMessage.find(withTimestamp: message.sentTimestamp!) != nil else { return } // The message has been deleted
diff --git a/SessionMessagingKit/Jobs/NotifyPNServerJob.swift b/SessionMessagingKit/Jobs/NotifyPNServerJob.swift
index c243fa30a..82c57b3f3 100644
--- a/SessionMessagingKit/Jobs/NotifyPNServerJob.swift
+++ b/SessionMessagingKit/Jobs/NotifyPNServerJob.swift
@@ -38,7 +38,9 @@ public final class NotifyPNServerJob : NSObject, Job, NSCoding { // NSObject/NSC
     }
     
     public func execute() -> Promise<Void> {
-        JobQueue.currentlyExecutingJobs.insert(id!)
+        if let id = id {
+            JobQueue.currentlyExecutingJobs.insert(id)
+        }
         let server = PushNotificationAPI.server
         let parameters = [ "data" : message.data.description, "send_to" : message.recipient ]
         let url = URL(string: "\(server)/notify")!