diff --git a/td/telegram/MessagesManager.cpp b/td/telegram/MessagesManager.cpp
index 927b14e5..e962cd87 100644
--- a/td/telegram/MessagesManager.cpp
+++ b/td/telegram/MessagesManager.cpp
@@ -9106,8 +9106,18 @@ void MessagesManager::on_update_secret_chat_state(SecretChatId secret_chat_id, S
   if (state == SecretChatState::Closed) {
     DialogId dialog_id(secret_chat_id);
     Dialog *d = get_dialog_force(dialog_id);
-    if (d != nullptr && d->new_secret_chat_notification_id.is_valid()) {
-      remove_new_secret_chat_notification(d, true);
+    if (d != nullptr) {
+      if (d->new_secret_chat_notification_id.is_valid()) {
+        remove_new_secret_chat_notification(d, true);
+      }
+      if (d->message_notification_group_id.is_valid() && get_dialog_pending_notification_count(d) == 0) {
+        CHECK(d->unread_mention_count == 0);  // there can't be unread mentions in secret chats
+        send_closure_later(G()->notification_manager(), &NotificationManager::try_reuse_notification_group_id,
+                           d->message_notification_group_id);
+        notification_group_id_to_dialog_id_.erase(d->message_notification_group_id);
+        d->message_notification_group_id = NotificationGroupId();
+        on_dialog_updated(d->dialog_id, "on_update_secret_chat_state");
+      }
     }
   }
 }
@@ -17984,6 +17994,11 @@ bool MessagesManager::add_new_message_notification(Dialog *d, Message *m, bool f
       return false;
     }
   }
+  if (d->dialog_id.get_type() == DialogType::SecretChat) {
+    if (td_->contacts_manager_->get_secret_chat_state(d->dialog_id.get_secret_chat_id()) == SecretChatState::Closed) {
+      return false;
+    }
+  }
 
   VLOG(notifications) << "Trying to " << (force ? "forcely " : "") << "add new message notification for "
                       << m->message_id << " in " << d->dialog_id
diff --git a/td/telegram/NotificationManager.cpp b/td/telegram/NotificationManager.cpp
index f1ab80d3..a4da34c7 100644
--- a/td/telegram/NotificationManager.cpp
+++ b/td/telegram/NotificationManager.cpp
@@ -41,6 +41,7 @@ void NotificationManager::on_flush_pending_notifications_timeout_callback(void *
   }
 
   auto notification_manager = static_cast<NotificationManager *>(notification_manager_ptr);
+  VLOG(notifications) << "Ready to flush pending notifications for notification group " << group_id_int;
   if (group_id_int > 0) {
     send_closure_later(notification_manager->actor_id(notification_manager),
                        &NotificationManager::flush_pending_notifications,
@@ -260,6 +261,9 @@ void NotificationManager::load_message_notifications_from_database(const Notific
   if (group.is_loaded_from_database || group.is_being_loaded_from_database) {
     return;
   }
+  if (group.total_count == 0) {
+    return;
+  }
 
   VLOG(notifications) << "Trying to load up to " << desired_size << " notifications in " << group_key.group_id
                       << " with " << group.notifications.size() << " current notifications";
@@ -444,6 +448,37 @@ NotificationGroupId NotificationManager::get_next_notification_group_id() {
   return current_notification_group_id_;
 }
 
+void NotificationManager::try_reuse_notification_group_id(NotificationGroupId group_id) {
+  if (!group_id.is_valid()) {
+    return;
+  }
+
+  VLOG(notifications) << "Trying to reuse " << group_id;
+  if (group_id != current_notification_group_id_) {
+    // may be implemented in the future
+    return;
+  }
+
+  auto group_it = get_group(group_id);
+  if (group_it != groups_.end()) {
+    CHECK(group_it->first.last_notification_date == 0);
+    CHECK(group_it->second.total_count == 0);
+    CHECK(group_it->second.notifications.empty());
+    CHECK(group_it->second.pending_notifications.empty());
+    CHECK(!group_it->second.is_being_loaded_from_database);
+    delete_group(std::move(group_it));
+
+    CHECK(running_get_chat_difference_.count(group_id.get()) == 0);
+
+    flush_pending_notifications_timeout_.cancel_timeout(group_id.get());
+    flush_pending_updates_timeout_.cancel_timeout(group_id.get());
+    pending_updates_.erase(group_id.get());
+  }
+
+  current_notification_group_id_ = NotificationGroupId(current_notification_group_id_.get() - 1);
+  G()->td_db()->get_binlog_pmc()->set("notification_group_id_current", to_string(current_notification_group_id_.get()));
+}
+
 NotificationGroupKey NotificationManager::get_last_updated_group_key() const {
   size_t left = max_notification_group_count_;
   auto it = groups_.begin();
@@ -1040,7 +1075,10 @@ void NotificationManager::send_add_group_update(const NotificationGroupKey &grou
 
 void NotificationManager::flush_pending_notifications(NotificationGroupId group_id) {
   auto group_it = get_group(group_id);
-  CHECK(group_it != groups_.end());
+  if (group_it == groups_.end()) {
+    CHECK(group_id.get() > current_notification_group_id_.get());
+    return;
+  }
 
   if (group_it->second.pending_notifications.empty()) {
     return;
@@ -1107,6 +1145,7 @@ void NotificationManager::flush_pending_notifications(NotificationGroupId group_
   if (group.notifications.size() > keep_notification_group_size_ + EXTRA_GROUP_SIZE) {
     // keep only keep_notification_group_size_ last notifications in memory
     group.notifications.erase(group.notifications.begin(), group.notifications.end() - keep_notification_group_size_);
+    group.is_loaded_from_database = false;
   }
 
   add_group(std::move(final_group_key), std::move(group));
diff --git a/td/telegram/NotificationManager.h b/td/telegram/NotificationManager.h
index 75c501ff..95f8529c 100644
--- a/td/telegram/NotificationManager.h
+++ b/td/telegram/NotificationManager.h
@@ -49,6 +49,8 @@ class NotificationManager : public Actor {
 
   NotificationGroupId get_next_notification_group_id();
 
+  void try_reuse_notification_group_id(NotificationGroupId group_id);
+
   void load_group_force(NotificationGroupId group_id);
 
   void add_notification(NotificationGroupId group_id, DialogId dialog_id, int32 date,