Why UseApplicationMessageReceivedHandler doesn't work for ManagedClient? MQTTnet C#

Question

When I run my program, everything is fine. However, this function doesn't execute anything. Starting from the line "this.Client.UseApplicationMessageReceivedHandler(e =>", the thing doesn't work. I wonder does UseApplicationMessageReceivedHandler work well with ManagedClient? Any idea on this?

private void SubscriptionHandler()
{
   this.Client.UseApplicationMessageReceivedHandler(e =>
   {
      try
      {
         string topic = e.ApplicationMessage.Topic;
         if (string.IsNullOrWhiteSpace(topic) == false)
         {
            string payload = Encoding.UTF8.GetString(e.ApplicationMessage.Payload);
            Console.WriteLine($"Topic: {topic}. Message Received: {payload}");
         }
      }
      catch (Exception ex)
      {
         Console.WriteLine(ex.Message, ex);
      }
   });
}