diff --git a/td/telegram/ConfigManager.cpp b/td/telegram/ConfigManager.cpp
index 8ca0c84c4..8cb135cf4 100644
--- a/td/telegram/ConfigManager.cpp
+++ b/td/telegram/ConfigManager.cpp
@@ -854,8 +854,13 @@ void ConfigManager::process_config(tl_object_ptr<telegram_api::config> config) {
     shared_config.set_option_string("photo_search_bot_username", config->img_search_username_);
   }
 
-  shared_config.set_option_integer("online_update_period_ms", config->online_update_period_ms_);
-  shared_config.set_option_integer("online_cloud_timeout_ms", config->online_cloud_timeout_ms_);
+  auto fix_timeout_ms = [](int32 timeout_ms) { return clamp(timeout_ms, 1000, 86400 * 1000); };
+
+  shared_config.set_option_integer("online_update_period_ms", fix_timeout_ms(config->online_update_period_ms_));
+
+  shared_config.set_option_integer("online_cloud_timeout_ms", fix_timeout_ms(config->online_cloud_timeout_ms_));
+  shared_config.set_option_integer("notification_cloud_delay_ms", fix_timeout_ms(config->notify_cloud_delay_ms_));
+  shared_config.set_option_integer("notification_default_delay_ms", fix_timeout_ms(config->notify_default_delay_ms_));
 
   // delete outdated options
   shared_config.set_option_empty("suggested_language_code");
@@ -884,9 +889,6 @@ void ConfigManager::process_config(tl_object_ptr<telegram_api::config> config) {
   //  shared_config.set_option_integer("offline_blur_timeout_ms", config->offline_blur_timeout_ms_);
   //  shared_config.set_option_integer("offline_idle_timeout_ms", config->offline_idle_timeout_ms_);
 
-  //  shared_config.set_option_integer("notify_cloud_delay_ms", config->notify_cloud_delay_ms_);
-  //  shared_config.set_option_integer("notify_default_delay_ms", config->notify_default_delay_ms_);
-
   //  shared_config.set_option_integer("push_chat_period_ms", config->push_chat_period_ms_);
   //  shared_config.set_option_integer("push_chat_limit", config->push_chat_limit_);
 }
diff --git a/td/telegram/NotificationManager.cpp b/td/telegram/NotificationManager.cpp
index e4daf1d0e..fe658cec9 100644
--- a/td/telegram/NotificationManager.cpp
+++ b/td/telegram/NotificationManager.cpp
@@ -53,12 +53,9 @@ void NotificationManager::start_up() {
   on_notification_group_count_max_changed();
   on_notification_group_size_max_changed();
 
-  online_cloud_timeout_ms_ =
-      G()->shared_config().get_option_integer("online_cloud_timeout_ms", DEFAULT_ONLINE_CLOUD_TIMEOUT_MS);
-  notification_cloud_delay_ms_ =
-      G()->shared_config().get_option_integer("notification_cloud_delay_ms", DEFAULT_ONLINE_CLOUD_DELAY_MS);
-  notification_default_delay_ms_ =
-      G()->shared_config().get_option_integer("notification_default_delay_ms", DEFAULT_DEFAULT_DELAY_MS);
+  on_online_cloud_timeout_changed();
+  on_notification_cloud_delay_changed();
+  on_notification_default_delay_changed();
 
   // TODO load groups
 }
@@ -428,6 +425,9 @@ void NotificationManager::on_notification_group_count_max_changed() {
     return;
   }
 
+  VLOG(notifications) << "Change max notification group count from " << max_notification_group_count_ << " to "
+                      << new_max_notification_group_count;
+
   if (max_notification_group_count_ != 0) {
     // TODO
   }
@@ -449,6 +449,9 @@ void NotificationManager::on_notification_group_size_max_changed() {
     return;
   }
 
+  VLOG(notifications) << "Change max notification group size from " << max_notification_group_size_ << " to "
+                      << new_max_notification_group_size;
+
   if (max_notification_group_size_ != 0) {
     // TODO
   }
@@ -458,4 +461,22 @@ void NotificationManager::on_notification_group_size_max_changed() {
       max_notification_group_size_ + max(EXTRA_GROUP_SIZE / 2, min(max_notification_group_size_, EXTRA_GROUP_SIZE));
 }
 
+void NotificationManager::on_online_cloud_timeout_changed() {
+  online_cloud_timeout_ms_ =
+      G()->shared_config().get_option_integer("online_cloud_timeout_ms", DEFAULT_ONLINE_CLOUD_TIMEOUT_MS);
+  VLOG(notifications) << "Set online_cloud_timeout_ms to " << online_cloud_timeout_ms_;
+}
+
+void NotificationManager::on_notification_cloud_delay_changed() {
+  notification_cloud_delay_ms_ =
+      G()->shared_config().get_option_integer("notification_cloud_delay_ms", DEFAULT_ONLINE_CLOUD_DELAY_MS);
+  VLOG(notifications) << "Set notification_cloud_delay_ms to " << notification_cloud_delay_ms_;
+}
+
+void NotificationManager::on_notification_default_delay_changed() {
+  notification_default_delay_ms_ =
+      G()->shared_config().get_option_integer("notification_default_delay_ms", DEFAULT_DEFAULT_DELAY_MS);
+  VLOG(notifications) << "Set notification_default_delay_ms to " << notification_default_delay_ms_;
+}
+
 }  // namespace td
diff --git a/td/telegram/NotificationManager.h b/td/telegram/NotificationManager.h
index bb9500497..95d6d2091 100644
--- a/td/telegram/NotificationManager.h
+++ b/td/telegram/NotificationManager.h
@@ -57,6 +57,12 @@ class NotificationManager : public Actor {
 
   void on_notification_group_size_max_changed();
 
+  void on_online_cloud_timeout_changed();
+
+  void on_notification_cloud_delay_changed();
+
+  void on_notification_default_delay_changed();
+
  private:
   static constexpr int32 DEFAULT_GROUP_COUNT_MAX = 10;
   static constexpr int32 DEFAULT_GROUP_SIZE_MAX = 10;
diff --git a/td/telegram/Td.cpp b/td/telegram/Td.cpp
index 0292ecf1c..15a40629d 100644
--- a/td/telegram/Td.cpp
+++ b/td/telegram/Td.cpp
@@ -3426,6 +3426,8 @@ bool Td::is_internal_config_option(Slice name) {
       return name == "language_pack_version";
     case 'm':
       return name == "my_phone_number";
+    case 'n':
+      return name == "notification_cloud_delay_ms" || name == "notification_default_delay_ms";
     case 'o':
       return name == "online_update_period_ms" || name == "online_cloud_timeout_ms";
     case 'r':
@@ -3489,6 +3491,12 @@ void Td::on_config_option_updated(const string &name) {
     send_closure(notification_manager_actor_, &NotificationManager::on_notification_group_count_max_changed);
   } else if (name == "notification_group_size_max") {
     send_closure(notification_manager_actor_, &NotificationManager::on_notification_group_size_max_changed);
+  } else if (name == "online_cloud_timeout_ms") {
+    return send_closure(notification_manager_actor_, &NotificationManager::on_online_cloud_timeout_changed);
+  } else if (name == "notification_cloud_delay_ms") {
+    return send_closure(notification_manager_actor_, &NotificationManager::on_notification_cloud_delay_changed);
+  } else if (name == "notification_default_delay_ms") {
+    return send_closure(notification_manager_actor_, &NotificationManager::on_notification_default_delay_changed);
   } else if (is_internal_config_option(name)) {
     return;
   }